Transmission method, reception method, transmission device, and reception device

ABSTRACT

According to one aspect of the present disclosure, a transmission method for enabling transmission of content using a broadcast wave and a communication channel includes: transmitting auxiliary information using at least the broadcast wave, the auxiliary information being information for synchronizing content transmission using the broadcast wave and content transmission using the communication channel when the content is transmitted using the broadcast wave and the communication channel, and the auxiliary information causing a reception side to perform the syncronization when the reception side receives the auxiliary information. Therefore, even if timing of starting reception of the content through the communication is delayed, the reception side can play back the content by a combination of the broadcasting and the communication.

BACKGROUND 1. Technical Field

The present disclosure relates to a data transmission method, a datareception method, a transmission device, and a reception device.

2. Description of the Related Art

Conventionally, a main transmission channel distributing content is abroadcast wave and, for example, there is an MPEG-2 TS (Moving PictureExperts Group-2 Transport Stream) as a media transport system widelyused in a current broadcasting system.

On the other hand, with recent progress of a network technology, thecontent can be distributed through a communication channel such as theInternet. That is, the content can be distributed through not only thebroadcast wave but also the communication channel, and the transmissionchannel through which the content can be distributed is diversified.

For example, NPTL 1 describes MMT (MPEG Media Transport) as a new mediatransport system in which the content is distributed by a combination ofthe broadcasting and the communication (see NPTL 1). For example, NPTL 1discloses a technology of accessing the communication content based ondata acquired through the broadcasting mainly used.

CITATION LIST Non-Patent Literature

NPTL 1: Information technology—High efficiency coding and media deliveryin heterogeneous environment—Part 1: MPEG media transport (MMT), ISO/IECDIS 23008-1

SUMMARY

In one general aspect, the techniques disclosed here feature atransmission method for enabling transmission of content using abroadcast wave and a communication channel, the transmission methodincludes: transmitting auxiliary information using at least thebroadcast wave, the auxiliary information being information forsynchronizing content transmission using the broadcast wave and contenttransmission using the communication channel when the content istransmitted using the broadcast wave and the communication channel, andthe auxiliary information causing a reception side to perform thesyncronization when the reception side receives the auxiliaryinformation.

Additional benefits and advantages of the disclosed embodiments willbecome apparent from the specification and drawings. The benefits and/oradvantages may be individually obtained by the various embodiments andfeatures of the specification and drawings, which need not all beprovided in order to obtain one or more of such benefits and/oradvantages.

It should be noted that general or specific embodiments may beimplemented as a system, a method, an integrated circuit, a computerprogram, a storage medium, or any selective combination thereof.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is a view illustrating an example of a data structure of serviceinformation in broadcasting and communication cooperation serviceaccording to a first exemplary embodiment;

FIG. 1B is a view illustrating an example of the data structure of theservice information in the broadcasting and communication cooperationservice of the first exemplary embodiment;

FIG. 2 is a view illustrating an example of an outline of a transmissionchannel identification descriptor of the first exemplary embodiment;

FIG. 3A is a view illustrating another example of the data structure ofthe service information in the broadcasting and communicationcooperation service of the first exemplary embodiment;

FIG. 3B is a view illustrating another example of the data structure ofthe service information in the broadcasting and communicationcooperation service of the first exemplary embodiment;

FIG. 4A is a flowchart illustrating an operation example on a receptionside in the broadcasting and communication cooperation service of thefirst exemplary embodiment;

FIG. 4B is a flowchart illustrating another operation example on thereception side in the broadcasting and communication cooperation serviceof the first exemplary embodiment;

FIG. 5 is a block diagram illustrating a configuration example of areception device of the first exemplary embodiment;

FIG. 6A is a view illustrating an example of a data structure of serviceinformation in the broadcasting and communication cooperation serviceaccording to a first modification of the first exemplary embodiment;

FIG. 6B is a view illustrating an example of the data structure of theservice information in the broadcasting and communication cooperationservice of the first modification of the first exemplary embodiment;

FIG. 7A is a flowchart illustrating an operation example on a receptionside in the broadcasting and communication cooperation service of thefirst modification of the first exemplary embodiment;

FIG. 7B is a flowchart illustrating another operation example on thereception side in the broadcasting and communication cooperation serviceof the first modification of the first exemplary embodiment;

FIG. 8 is a block diagram illustrating a configuration example of areception device of the first modification of the first exemplaryembodiment;

FIG. 9 is a flowchart illustrating an operation example on a receptionside in broadcasting and communication cooperation service according toa second modification of the first exemplary embodiment;

FIG. 10 is a block diagram illustrating a configuration example of areception device of the second modification of the first exemplaryembodiment;

FIG. 11 is a view illustrating an example of a data structure of serviceinformation in the broadcasting and communication cooperation serviceaccording to a fourth modification of the first exemplary embodiment;

FIG. 12 is a flowchart illustrating an operation example on a receptionside in the broadcasting and communication cooperation service of thefourth modification of the first exemplary embodiment;

FIG. 13A is a view illustrating a syntax example of a locationinformation descriptor of the fourth modification of the first exemplaryembodiment;

FIG. 13B is a view illustrating a syntax example of the locationinformation descriptor of the fourth modification of the first exemplaryembodiment;

FIG. 13C is a view illustrating a syntax example of the locationinformation descriptor of the fourth modification of the first exemplaryembodiment;

FIG. 13D is a view illustrating a syntax example of the locationinformation descriptor of the fourth modification of the first exemplaryembodiment;

FIG. 14 is a flowchart illustrating an operation example on a receptionside in broadcasting and communication cooperation service according toa sixth modification of the first exemplary embodiment;

FIG. 15 is a flowchart illustrating another operation example on thereception side in the broadcasting and communication cooperation serviceof the sixth modification of the first exemplary embodiment;

FIG. 16 is a flowchart illustrating an operation example on a receptionside in broadcasting and communication cooperation service according toa seventh modification of the first exemplary embodiment;

FIG. 17 is a block diagram illustrating a configuration example of areception device of the seventh modification of the first exemplaryembodiment;

FIG. 18A is a view illustrating a description example of defaultplayback control information according to a second exemplary embodiment;

FIG. 18B is a view illustrating a video display example according tolayout information of the default playback control information in FIG.18A;

FIG. 19A is a view illustrating an example of application controlinformation of the second exemplary embodiment;

FIG. 19B is a view illustrating a video display example according to thelayout information of the application control information in FIG. 19A;

FIG. 20A is a view illustrating another description example of thedefault playback control information of the second exemplary embodiment;

FIG. 20B is a view illustrating a video display example according to thelayout information of the default playback control information in FIG.20A;

FIG. 21A is a view illustrating an example of the application controlinformation of the second exemplary embodiment;

FIG. 21B is a view illustrating a video display example according to thelayout information of the application control information in FIG. 21A;

FIG. 22 is a flowchart illustrating an operation example on a receptionside of the second exemplary embodiment;

FIG. 23 is a block diagram illustrating a configuration example of areception device of the second exemplary embodiment;

FIG. 24 is a view illustrating an example of a data structure of serviceinformation in broadcasting and communication cooperation serviceaccording to a third exemplary embodiment;

FIG. 25 is a view illustrating an example of information included in aprogram configuration information descriptor of the third exemplaryembodiment;

FIG. 26 is a view illustrating an example of information included in alocation information descriptor of the third exemplary embodiment;

FIG. 27 is a view illustrating an example of a location type included inthe location information descriptor of the third exemplary embodiment;

FIG. 28 is a view illustrating an example of information included in anasset configuration information descriptor of the third exemplaryembodiment;

FIG. 29 is a flowchart illustrating a reception method in thebroadcasting and communication cooperation service of the thirdexemplary embodiment; and

FIG. 30 is a block diagram illustrating a configuration example of areception device of the third exemplary embodiment.

DESCRIPTION OF EMBODIMENTS

(Underlying Knowledge Forming Basis of the Present Disclosure)

Services (broadcasting and communication cooperation service) thatdistribute the content by the combination of the broadcasting and thecommunication are currently studied. Among them, the most promisingsystem is one that accesses the content (hereinafter, referred to ascommunication content) acquired through the communication based on thedata acquired through the broadcasting mainly used. As to reception-sideoperation to receive the content in the broadcasting and communicationcooperation service during viewing start, similarly to conventionalservice that distributes the content only through the broadcasting, itis conceivable that the reception of the content is started by audio orvideo coded data or an MPEG-2-system data carousel after acquisition ofservice information.

However, the service information that can be acquired by theconventional service is not compatible with operation to rapidly accessthe communication content or operation to select and receive only thebroadcasting content. Therefore, in the case that the broadcasting andcommunication cooperation service is performed using the conventionalservice information, there is a problem in that processing relevant toan analysis of the service information increases or timing of startingthe acquisition of the communication content is delayed.

According to one aspect of the present disclosure, a transmission methodfor enabling transmission of content using a broadcast wave and acommunication channel, the transmission method includes an informationtransmission step of transmitting auxiliary information using at leastthe broadcast wave, the auxiliary information for synchronizing contenttransmitted using the broadcast wave and content transmitted using thecommunication channel when the content is transmitted using thebroadcast wave and the communication channel, the auxiliary informationcausing a reception side to synchronize the content transmitted usingthe broadcast wave and the content transmitted using the communicationchannel when the reception side receives the auxiliary information.

The present disclosure can provide the transmission method in which thereception side plays back the content by the combination of thebroadcasting and the communication even if the timing of starting thereception of the content through the communication is delayed. Morespecifically, when the content is transmitted using the broadcast waveand the communication channel, the auxiliary information is transmittedin order to synchronize the content transmitted using the broadcast waveand the content transmitted using the communication channel, so that thereception side can synchronize the content transmitted using thebroadcast wave and the content transmitted using the communicationchannel when receiving the auxiliary information.

In the information transmission step, the auxiliary information may betransmitted in advance of the transmission of the content, and theauxiliary information further may include location informationindicating an acquisition destination of the content or informationindicating an acquisition destination of the location information.

In the auxiliary information transmission step, the auxiliaryinformation may be transmitted while difference information between areference clock of the content transmitted using the broadcast wave anda reference clock of the content transmitted using the communicationchannel is included in the auxiliary information.

In the auxiliary information transmission step, when the referenceclocks of the pieces of content differ, the auxiliary informationtransmission may cause the reception side to achieve the synchronizationthrough synchronization of the reference clock of the contenttransmitted using the communication channel with the reference clock ofthe content transmitted using the broadcast wave based on the differenceinformation.

The transmission method may further include a generation step ofgenerating the content in a format compatible with MMT (MPEG MediaTransport), and a content transmission step of transmitting the contentin the format generated in the generation step.

In the generation step, the content may be generated while the auxiliaryinformation is included in message information that is information onthe acquisition of the content.

According to another aspect of the present disclosure, a receptionmethod includes: a reception step of receiving content transmitted usinga broadcast wave and content transmitted using a communication channel;and a playback step of playing back the content transmitted using thebroadcast wave and the content transmitted using the communicationchannel while synchronizing the pieces of content, when auxiliaryinformation for synchronizing the content transmitted using thebroadcast wave and the content transmitted using the communicationchannel is received.

In the reception step, the content may be received by acquiring thecontent based on location information indicating an acquisitiondestination of the content when the auxiliary information is received inadvance of the reception of the content and the auxiliary informationincludes the location information.

In the reception step, the content may be received by acquiring locationinformation indicating an acquisition destination of the content basedon information indicating an acquisition destination of the locationinformation, and acquiring the content based on the acquired locationinformation when the auxiliary information is received in advance of thereception of the content and the auxiliary information includes theinformation indicating the acquisition destination of the locationinformation.

In the playback step, the content may be played back while thesynchronization is achieved through synchronization of the referenceclock of the content transmitted using the communication channel withthe reference clock of the content transmitted using the broadcast wavebased on the difference information when the auxiliary informationincluding difference information between a reference clock of thecontent transmitted using the broadcast wave and a reference clock ofthe content transmitted using the communication channel is received inthe reception step and the reference clock of the content transmittedusing the broadcast wave differs from the reference clock of the contenttransmitted using the communication channel.

According to still another aspect of the present disclosure, atransmission device that can transmit content using a broadcast wave anda communication channel, the transmission device includes an informationtransmitter that transmits auxiliary information using at least thebroadcast wave, the auxiliary information for synchronizing contenttransmitted using the broadcast wave and content transmitted using thecommunication channel when the content is transmitted using thebroadcast wave and the communication channel, the auxiliary informationcausing a reception side to synchronize the content transmitted usingthe broadcast wave and the content transmitted using the communicationchannel when the reception side receives the auxiliary information.

According to yet another aspect of the present disclosure, a receptiondevice includes: a reception part that receives content transmittedusing a broadcast wave and content transmitted using a communicationchannel; and a playback part that plays back the content transmittedusing the broadcast wave and the content transmitted using thecommunication channel while synchronizing the pieces of content, whenauxiliary information for synchronizing the content transmitted usingthe broadcast wave and the content transmitted using the communicationchannel is received.

These overall or specific aspects may be implemented by a transmissionmethod, a transmission device, a reception method, a reception device,an integrated circuit, a computer program, and a recording medium suchas a computer-readable CD-ROM, or implemented by any combination of thedata reception method, the integrated circuit, the computer program, andthe recording medium.

Hereinafter, a transmission method and a reception method according toan exemplary embodiment of the present disclosure will specifically bedescribed with reference to the drawings.

The following exemplary embodiment illustrates a specific example of thepresent disclosure. The following numerical value, shape, material,component, disposition and connection form of the component, step, andstep sequence indicated in the exemplary embodiment are described onlyby way of example, but do not limit the present disclosure. In thefollowing components of the exemplary embodiment, the component that isnot described in an independent claim indicating a highest concept isdescribed as an optional component.

First Exemplary Embodiment

A transmission method for transmitting and receiving content inbroadcasting and communication cooperation service will be described ina first exemplary embodiment.

[Transmission Method]

In the first exemplary embodiment, the transmission side transmits thecontent (data or asset) using the broadcast wave and the communicationchannel, and transmits the service information in advance of the contenttransmission.

[Service Information]

As used herein, the service information means a series of informationrelative to the content reception or meta-data acquisition, such asinformation used to acquire data relevant to audio or video or databroadcasting after tuning operation (after tuning), or information onEPG (Electric Program Guide).

The current broadcasting is mainly transmitted using an MPEG-2 TS(Transport Stream) section, and includes a PAT (Program AssociationTable), a PMT (Program Map Table), an NIT (Network Information Table), aCAT (Conditional Access Table), or an EIT (Event Information Table)defined by ARIB (Association of Radio Industries and Businesses).

In the first exemplary embodiment, MMT (MPEG Media Transport)standardized by MPEG will be described as an example of abroadcasting-side multiplexing format in the broadcasting andcommunication cooperation service. However, the multiplexing format isnot limited to the MMT. Alternatively, other multiplexing formats suchas TS and MPEG-DASH (Dynamic Adaptive Streaming over HTTP) may be used.

The service information of the first exemplary embodiment is transmittedin a data structure that can be stored in the multiplexing format. Forexample, in the MMT, the service information is transmitted by a tablesuch as an MPT (MMT Package Table) or message information such as a PA(Package Access) message. In each table, similarly to the TS, auxiliaryinformation can be described using a descriptor.

FIGS. 1A and 1B are views illustrating an example of the data structureof the service information in the broadcasting and communicationcooperation service of the first exemplary embodiment. Morespecifically, FIG. 1A illustrates the MPT including a transmissionchannel identification descriptor, and FIG. 1B illustrates an example inwhich information on a transmission channel of an asset constituting,for example, a package is described as attribute information in thetransmission channel identification descriptor of FIG. 1A.

(Attribute Information)

1) Information indicating whether the asset constituting the package isto be transmitted by (1) a method in which only the broadcasting is usedor (2) a method in which the broadcasting and the communication arecombined may be included as the attribute information.

Information indicating whether the audio and video data of a main storyis to be transmitted by (1) the method in which only the broadcasting isused or (2) the method in which the broadcasting and the communicationare combined may be included as the attribute information. Other piecesof meta-data such as the audio, the video, a still image, and an HTMLfile, which are different from the main story, can be acquired from acommunication network based on the information even if the main story istransmitted only through the broadcasting.

2) Information indicating the relation between the pieces of datatransmitted through the broadcasting and communication may be includedin the attribute information when the audio or video data is transmittedby the combination of the broadcasting and the communication.

For example, in the case that scalability (time resolution (for example,60 fps→120 fps), spatial resolution (for example, 4 k→8 k), and bitdepth (for example, 8 bits→10 bits)) is provided, the attributeinformation can indicate that the transmission is performed using abasic layer in the broadcasting, and that the transmission is performedusing an extension layer in the communication. The attribute informationmay indicate that, although a frame rate is 60 fps only for thebroadcasting data, the frame rate can be improved up to 120 fps when thecommunication data is combined. The attribute information may indicatethat backup data of the broadcasting is transmitted through thecommunication. Thus, in the case that a reception status is degraded dueto rain attenuation, the transmission side can switch the transmissionusing the attribute information so as to transmit the data through thecommunication.

The attribute information may indicate information identifying theassets correlated with each other. For example, the attributeinformation may indicate an asset ID of the basic layer and an asset IDof the extension layer corresponding to the basic layer.

In the MMT, the identical asset can also be transmitted using aplurality of transmission channels. Accordingly, the attributeinformation may indicate that the identical asset is to be transmittedby the combination of the broadcasting and the communication. At thispoint, identification information (such as the asset ID) on the assetmay separately be indicated. For example, the information identifyingthe assets correlated with each other may be indicated by an individualtransmission channel identification descriptor of each asset asillustrated in FIG. 2. FIG. 2 is a view illustrating an example of anoutline of the transmission channel identification descriptor of thefirst exemplary embodiment. For example, the individual transmissionchannel identification descriptor in FIG. 2 may indicate informationidentifying the asset of the basic layer and the asset of the extensionlayer, or indicate the asset ID of the corresponding basic layer in thecase that the asset is the extension layer.

The attribute information may indicate a list of assets included in agroup of the broadcasting assets and a list of assets included in agroup of the communication assets. In the case that the assettransmitted by the combination of the broadcasting and the communicationexists, the asset may separately be grouped.

3) Information indicating whether the audio or video transmitted throughthe broadcasting and the audio or video transmitted through thecommunication are to be synchronously played back may be included as theattribute information.

4) Information indicating whether audio or video clock informationtransmitted through the broadcasting is identical to audio or videoclock information transmitted through the communication may be includedas the attribute information.

The attribute information may indicate individual information as anindividual field, or information indicating a service type may bedefined to identify the individual information by the service type. Theattribute information may be described in a format different from thatof the descriptor.

The transmission channel identification descriptor may be stored in atable or message indicating information in a package unit different fromthe MPT. The content of the transmission channel identificationdescriptor may be described as a data structure different from that ofthe descriptor.

In the case that the plurality of packages are transmitted, a table ormessage indicating a list of packages may be defined to indicate suchinformation as the transmission channel identification descriptor beingthe information in the package unit as the attribute information on thepackage.

FIGS. 3A and 3B are views illustrating another example of the datastructure of the service information in the broadcasting andcommunication cooperation service of the first exemplary embodiment.

As illustrated in FIGS. 3A and 3B, for the location information on eachasset, the asset transmitted through the broadcasting and the assettransmitted through the communication may separately be stored in theMPTs. At this point, the package attribute information can be stored inthe MPT transmitted through the transmission channel constituting anentry point of the service. For example, in the case that thebroadcasting constitutes the entry point, the attribute information onthe package is stored in the MPT transmitted through the broadcasting.The MPT can be identified by table_id.

In the MMT standard, because a value of table_id of the reference MPT isdefined as zero, table_id of the MPT corresponding to one of thetransmission channels constituting the entry point can be set to zerowhile table_id of the MPT corresponding to the other transmissionchannel is set to 1 or more.

The MPT of the broadcasting asset may be transmitted through thebroadcasting while the MPT of the communication asset is transmittedthrough the communication.

The pieces of location information on the broadcasting and communicationassets may be stored in one MPT. In this case, the pieces of locationinformation on the broadcasting and communication assets cancontinuously be stored so as to be easily identified. For example, inthe case that N1 broadcasting assets and N2 communication assets exist,after the pieces of information on the N1 broadcasting assets arecontinuously described, the pieces of information on the N2communication assets are continuously described. The transmissionchannel identification descriptor may indicate that the N1 assets aretransmitted through the broadcasting while the N2 assets are transmittedthrough the communication.

Thus, on the transmission side, the service information is transmittedwhile including the transmission channel identification descriptor ofthe auxiliary information. Thus, on the reception side, only byacquiring the service information including the auxiliary information,whether the communication data is included or the dependencerelationship between the broadcasting data and the communication datacan previously be acquired from the package attribute informationdescribed in the transmission channel identification descriptor withoutanalyzing the information on each asset.

In particular, a delay time relevant to the start of receptionprocessing can be shortened in receiving the communication data.

[Transmission Device]

For example, the transmission device of the first exemplary embodimentis a content transmission device that can transmit the content using thebroadcast wave and the communication channel, and generates the packageattribute information such as the transmission channel identificationdescriptor as the auxiliary information, and transmits the auxiliaryinformation included in the service information.

The transmission device of the first exemplary embodiment mayperiodically transmit the service information. In updating the contentof the service information, the newly-updated content is reflected inthe service information immediately after the update.

The entry point is not limited to the broadcasting, but the entry pointmay be the communication or the entry may be performed through both thebroadcasting and the communication. In the case that the entry isperformed through both the broadcasting and the communication, theinformation in the package unit is transmitted from at least thebroadcasting and communication transmission devices.

In receiving the content of the broadcasting and communicationcooperation service on the reception side, the data transmitted throughboth the transmission channels is not necessarily received. For example,only the broadcasting data may be received and played back. At thispoint, because necessity of the information necessary for the receptionside to receive the communication data is eliminated during thereception of the broadcasting data, the transmission side may transmitthe information necessary for the reception of the communication datausing the communication. That is, the transmission side may transmit theinformation on the package unit through the transmission channelconstituting the entry point, and transmit the information unique to thetransmission channel such as the broadcasting and the communicationthrough each transmission channel (for example, FIG. 2). In thefollowing description, it is assumed that the broadcasting is the entrypoint.

Therefore, the service information unique to each transmission channelcan be generated and transmitted by the transmission device in eachtransmission channel. However, information such as the asset locationinformation which is transmitted by the MPT may be transmitted throughthe broadcasting, since a delay time relevant to the communication-sideasset acquisition start can be decreased by collectively acquiring suchinformation.

(Example of Information Unique to Communication)

An example of the information unique to the communication (acommunication network such as the Internet and a CDN (Content DeliveryNetwork)) will be described below.

1) Information, such as an FEC (Forward Error Correction) system and aparameter, which relates to the FEC in the packet transmitted throughthe communication

2) Information, such as a packet loss ratio, jitter at a packet arrivalclock time, an RTT (Round Trip Time), and an end-to-end delay in thecommunication transmission channel, which relates to QoS (Quality ofService) control

3) Information, such as a buffering time and a buffering amount, whichrelates to buffering until the decoding is started since the asset datais received

Even in the broadcasting, particularly in mobile broadcasting (forexample, one-segment broadcasting in Japan), the FEC and the QoS areimportant, and the parameters in the FEC and the QoS are different fromthose of the communication channel. Therefore, the information unique tothe broadcasting may be transmitted only through the broadcasting.

On the other hand, in the communication, the plurality of pieces ofaudio or video data such as the bit rate and the frame rate can beselected according to a band of the communication network. At thispoint, information correlating the attribute information (such as thebit rate) and the asset ID of the selectable data with each other may betransmitted. The correlating information may be transmitted through thebroadcasting.

Information indicating whether the plurality of selectable assets existmay be indicated as the correlating information, or a list of selectableassets may be indicated as the correlating information in the case thatthe plurality of selectable assets exist.

[Reception Method]

In the first exemplary embodiment, the reception side starts thereception (acquisition) of the content after acquiring the serviceinformation. A reception method of the first exemplary embodiment willbe described below with reference to the drawings.

FIG. 4A is a flowchart illustrating an operation example on thereception side in the broadcasting and communication cooperation serviceof the first exemplary embodiment. FIG. 4A illustrates an example of theoperation in which the reception device acquires the transmissionchannel identification descriptor of the first exemplary embodiment todecide the asset to be received.

For example, the PA message or MPT table included in the MPT message isacquired as the service information transmitted through the transmissionchannel constituting the entry point, and the transmission channelidentification descriptor included in the PA message or MPT table isacquired.

Information on the transmission channel identification descriptorinformation is interpreted regarding, for example, whether the asset isto be transmitted by the combination of the broadcasting and thecommunication and, if both of the transmission channels are to be used,an independence relationship between the broadcasting and communicationassets (Step S101).

The message such as the PA message is stored in a payload of the packetsuch as the MMT packet, and a type of storage data is indicated by apacket header. Accordingly, in receiving the MMT package, the MMT packetof the PA message is acquired by referring to an ID number(corresponding to packet_id in the MMT packet) at the packet header.

The asset to be received is decided based on a playback capability of aterminal or availability of the communication channel (Step S102).

An example of the asset decision method will be described below.

1) In the case that the reception device is not connected to thecommunication network, it is determined that only the asset is receivedthrough the broadcasting. At this point the asset transmitted by thecombination of the broadcasting and the communication is not received.

2) When the video basic layer is transmitted through the broadcastingwhile the video extension layer is transmitted through thecommunication, it is decided that the video basic layer is to bereceived through the broadcasting in the case that only the video basiclayer can be played back, and it is decided that the video basic layeris to be received through the broadcasting while the video extensionlayer is to be received through the communication in the case that boththe video basic layer and the video extension layer can be played back.For example, it is assumed that the time scalability of 60 fps isimplemented only by the basic layer, and that the time scalability of120 fps is implemented by the basic layer and the extension layer. Atthis point, the data is received only through the broadcasting when thereception device can decode and display the data only up to 60 fps, andthe pieces of data are received through both the broadcasting and thecommunication when the reception device can decode and display the dataup to 120 fps.

3) According to the band of the communication network to which thereception device is connected, the receivable asset is decided from theplurality of assets having different bit rates at which the transmissionis performed through the communication. At this point, it is assumedthat information such as the bit rate of each asset is separatelytransmitted in the service information. In the case that the stablyreceivable asset does not exist due to poor reception conditions causedby congestion of the communication network, it may be decided that thecommunication-side data is not to be received.

4) In the case that the backup data is transmitted through thecommunication in preparation for degradation of a broadcasting receptionenvironment, the asset to be acquired may be decided when thebroadcasting reception environment degrades. In this case, the receptiondevice may monitor the broadcasting reception environment, determinewhether the communication asset is to be received based on an index suchas an error rate in the reception data, and perform the receptionprocessing.

5) When the data (such as the data in the video extension layer) that isplayed back in synchronization with the audio or video data of the mainstory transmitted through the broadcasting is received through thecommunication, sometimes such special operation that the data isbuffered before the playback start is required in order to assure thesynchronization between the data received through the broadcasting andthe data received through the communication. In such cases, only theasset that is not required to be strictly synchronized (for example, thesynchronization in frame unit) with the data received through thebroadcasting may be received through the communication. For example, itmay be decided that the assets of HTML data, a still image, and a videoimage in which the strict synchronization is not required are acquiredthrough the communication.

The description is made referring to the flowchart in FIG. 4A.

In Step S103, whether the asset transmitted through the communication isto be received is decided (determined). The flow goes to S104 when thedecision (determination) that the asset is to be received is made (YESin S103), and the flow goes to S105 when the decision (determination)that the asset is not to be received is made (NO in S103).

In S104, the asset is received through both the broadcasting andcommunication transmission channels. In S105, the asset is received onlythrough the broadcasting.

FIG. 4B is a flowchart illustrating another operation example on thereception side in the broadcasting and communication cooperation serviceof the first exemplary embodiment.

In FIG. 4B, compared with FIG. 4A, a step of receiving the serviceinformation unique to the communication (Step S106) is added in the casethat the service information is transmitted through the communication.Because other steps are similar to those in FIG. 4A, the description isomitted.

It is assumed that in the case that the service information unique tothe broadcasting exists, such information is separately received inanother step (not illustrated).

Only the broadcasting asset is to be received in the case that thereception device is not compatible with the broadcasting andcommunication cooperation service. In this case, the asset transmittedby the combination of the broadcasting and the communication is notreceived.

[Reception Device]

FIG. 5 is a block diagram illustrating a configuration example of areception device of the first exemplary embodiment. FIG. 5 illustratesthe configuration example of the reception device that performs thereception method in FIG. 4A.

Reception device 100 in FIG. 5 includes identification informationacquisition part 101, asset decision part 102, determination part 103,broadcasting receiver 104, and communication receiver 105.

Identification information acquisition part 101 has a function ofperforming Step S101 in FIG. 4A. Specifically, identificationinformation acquisition part 101 acquires the service informationtransmitted through the transmission channel constituting the entrypoint, and acquires the transmission channel identification descriptor(auxiliary information) included in the service information.Identification information acquisition part 11 interprets theinformation on the transmission channel identification descriptor.

Asset decision part 102 has a function of performing Step S102 in FIG.4A, and decides the asset to be received based on the playbackcapability of the terminal or the availability of the communicationchannel.

Determination part 103 has a function of performing Step S103 in FIG.4A, and decides (determines) whether the asset transmitted through thecommunication is to be received. Specifically, determination part 103determines whether the communication data is to be received. When thecommunication data is to be received, broadcasting receiver 104 andcommunication receiver 105 receive the data of the asset decided in Step102.

When determination part 103 determines that the communication data isnot to be received, the data is received using only broadcastingreceiver 104.

(First Modification)

An example of the case that the data is transmitted through thebroadcasting using the TS while the data is transmitted through thecommunication using DASH or RTP (Real-time Transport Protocol) will bedescribed in a first modification.

FIGS. 6A and 6B are views illustrating an example of the data structureof the service information in the broadcasting and communicationcooperation service of the first modification of the first exemplaryembodiment. FIG. 6A illustrates an example in which the information onthe data transmitted through the communication is stored in the PMT.FIG. 6B illustrates a data structure example of the transmission channelidentification descriptor of the first modification.

In first modification, the transmission channel identificationdescriptor indicating the attribute information in FIGS. 1A and 1B isstored in the PMT that is of an example of the service information.

Only the location information on the data transmitted by the TS isindicated in the program information in the TS such as the PMT.Therefore, in first modification, the location information on thecommunication-side data is stored in the transmission channelidentification descriptor when the content data is transmitted incombination with the communication. More specifically, the attributeinformation includes flag information indicating whether thecommunication is to be also used. Thus, the transmission side canperform the selection whether to include location information on thecommunication-side data according to a value of the flag information.The location information is not necessarily stored in the transmissionchannel identification descriptor. A descriptor may separately bedefined so as to store the location information therein.

(Location Information)

The location information means information indicating the acquisitiondestination of the data. The PID corresponds to the location informationfor the TS, and the URL or URI corresponds to the location informationfor the communication.

MPD (Media Presentation Description) of the DASH or SDP (SessionDescription Protocol) of the RTP may be stored as the locationinformation.

Not only the data entity of the MPD or SDP location information, butalso information indicating the acquisition destination of the dataentity of the location information may be stored in the locationinformation. For example, the information indicating the acquisitiondestination of the data entity of the location information isinformation indicating the URL for acquiring the MPD. However, if theinformation indicating the acquisition destination of the data entity ofthe location information is stored in the location information, a delayis generated because the data entity of the location information isseparately acquired. Therefore, desirably the data entity is directlystored in the location information from the viewpoint of reducing thedelay until the communication-side data reception start.

The MPD of the DASH has a large size because various pieces ofinformation on the acquisition destination of the content are includedin the MPD of the DASH. Accordingly, instead of directly storing the MPDin the location information, subset information only including the URLof the acquisition destination of the content and information on a DTS(Decoding Time Stamp) or a PTS (Presentation Time Stamp) of the segmentmay be stored.

Desirably the update of the content of the location information such asthe MPD can be dealt with.

For example, a version number may be provided to the locationinformation. Thus, the location information can be acquired again whenthe version number is updated. The information such as the transmissionchannel identification descriptor in the periodically-transmitted PMTmay sequentially be checked in order to confirm whether the versionnumber is updated. Alternatively, since the sequential checkingprocessing is heavy, section data to store the location information andthe like may separately be generated (hereinafter, referred to as atransmission channel identification section), and periodically betransmitted.

In the reception device, whether the location information is updated canbe determined when the version number is confirmed in the transmissionchannel identification section. The attribute information or thelocation information may be transmitted in both the program informationsuch as the PMT and the transmission channel identification section.Alternatively, only the location information may be stored in thetransmission channel identification section.

After the acquisition of the communication-side data is started based onthe location information acquired from the broadcasting, the updatecontent of the location information may be acquired through thecommunication. At this point, because the acquisition destination of thelocation information is required, the acquisition destination of thelocation information may be stored in the broadcasting transmissionchannel identification descriptor together with the data entity of thelocation information.

In the reception device, the update content can be acquired through thecommunication by accessing the acquisition destination of the locationinformation at fixed intervals.

In the case that a message exchange mechanism exists between adistribution server of the DASH content and the reception device, thedistribution server may issue a message notifying that the locationinformation is updated to the reception device. In the reception device,the location information may be acquired again when the message isreceived.

In first modification, the information on the data transmitted throughthe communication is stored in the PMT. Alternatively, the attributeinformation or the location information may be transmitted by a sectiondifferent from the PMT.

The communication-side data acquisition method may be changed based onwhether the data transmitted through the communication is to be playedback in synchronization with the audio or video of the broadcasting.

For example, in the case that the synchronization playback is performed,the communication-side data can be accessed from the program informationon the broadcasting as described above. In the case that thesynchronization playback is not performed, information for accessing thecommunication-side data may be transmitted by data broadcasting using anAIT (Application Information Table) defined by a hybridcastspecification in ARIB (Association of Radio Industries and Businesses).In the reception device, the AIT is received in the format of the table,carousel, or the like, and the communication-side data is acquired basedon the content of the AIT. The playback of the acquiredcommunication-side data is started when an event message transmitted bythe data broadcasting is received.

The information such as the AIT may be used even in the case that thebroadcasting data and the communication data are to be synchronouslyplayed back. At this point, it is assumed that the clock time theplayback of the communication-side data is to be started or ended isseparately indicated in the data broadcasting. In the reception device,the communication-side data is played back according to these clocktimes.

In the MPD of the DASH or the SDP of the RTP, the content playback startclock time or the content decoding start clock time can be indicated,and these clock times are specified based on the reference clock, suchas UTC (Coordinated Universal Time), which is defined in eachmultiplexing or transmission system. The PTS (Presentation Time Stamp)or DTS (Decoding Time Stamp) of an individual video frame or audiosample are also set based on the reference clock. On the other hand, inthe broadcasting, because a PCR (Program Clock Reference) serves as thereference clock, information indicating a correlation between thereference clocks of the broadcasting-side data and communication-sidedata is required when the broadcasting-side data and thecommunication-side data are to be synchronously played back.

Accordingly, the information indicating the correlation between thereference clocks of the broadcasting-side data and communication-sidedata may be included in the program information, such as the PMT, on thebroadcasting. For example, the information indicating the correlationbetween the reference clocks of the broadcasting-side data andcommunication-side data may be information indicating that the clocktime at which the value of the broadcasting PCR is N1 is identical tothe clock time at which the value of the communication UTC is N2. Thesepieces of information may be included in the MPD or SDP.

Transport layer protocol information indicating whether thecommunication-side data is to be transmitted by a UDP (User DatagramProtocol) or a TCP (Transmission Control Protocol) may be indicated inthe transmission channel identification descriptor. Thus, the receptiondevice can open a port to be used in each protocol or determine whetherthe reception device is compatible with the protocol to be used.

For example, whether the multiplexing format is compatible with the DASHor RTP may be identified by indicating the identification information onthe multiplexing format of the communication-side data.

[Reception Method]

An operation example of the reception device in the case that the datais received through the broadcasting using the TS while the data isreceived through the communication using the DASH or RTP (Real-timeTransport Protocol) will be described as the reception method of firstmodification with reference to the drawings.

FIG. 7A is a flowchart illustrating an operation example on thereception side in the broadcasting and communication cooperation serviceof the first modification of the first exemplary embodiment. FIG. 7Aillustrates an operation example of the reception device when theattribute information or the location information is stored in theprogram information on the broadcasting.

The operation in each step (Steps S201 to S205) is similar to that ofthe flowchart in FIG. 4A. However, although the broadcasting-side dataand the communication-side data are unified by the asset of the MMTpackage as illustrated in FIG. 4A, the data is received through thebroadcasting using the TS while the data is received through thecommunication using the DASH or RTP as illustrated in FIG. 7A. Becauseother points are similar to those in FIG. 4A, the detailed descriptionis omitted.

FIG. 7B is a flowchart illustrating another operation example on thereception side in the broadcasting and communication cooperation serviceof the first modification of the first exemplary embodiment. FIG. 7Billustrates an example of the operation in which the attributeinformation and the access information for acquiring the locationinformation are stored in the program information of the broadcastingwhile the entity of the location information is not stored.

Because Step S301 is similar to Step S201, the description is omitted.

In Step S302, whether the communication-side data is to be received isdecided (determined). The flow goes from S303 to S304 when thecommunication-side data is to be received, and the flow goes from S303to S306 when the communication-side data is not to be received.

In Step S304, the location information is acquired according to theacquisition destination of the location information on thecommunication-side data included in the program information on thebroadcasting.

On the other hand, in Step S305, the communication-side data is acquiredbased on the location information acquired in S304, and the broadcastingdata is acquired. In S306, only the data transmitted through thebroadcasting is acquired.

(Attribute Information)

The attribute information is similar to that of the first exemplaryembodiment. Since the MMT is described by way of example in the firstexemplary embodiment, an example of the case that the data is receivedthrough the broadcasting using the TS while the data is received throughthe communication using the DASH or RTP will be described below.

1) Information indicating whether the audio and video data constitutingthe content is to be transmitted by (1) the method in which only thebroadcasting is used or (2) the method in which the broadcasting and thecommunication are combined may be included as the attribute information.

Information indicating whether the audio and video data is to betransmitted by (1) the method in which only the broadcasting is used or(2) the method in which the broadcasting and the communication arecombined may be included as the attribute information. Other pieces ofmeta-data such as the audio, the video, the still image, and the HTMLfile can be acquired from the communication network separately from themain story based on the information even if the main story istransmitted only through the broadcasting.

2) Information indicating the relation between the pieces of datatransmitted through the broadcasting and communication may be includedin the attribute information when the audio or video is transmitted bythe combination of the broadcasting and the communication.

For example, in the case that scalability (time resolution (for example,60 fps→120 fps), spatial resolution (for example, 4 k→8 k), and bitdepth (for example, 8 bits→10 bits)) is provided, the attributeinformation can indicate that the transmission is performed using thebasic layer in the broadcasting, and that the transmission is performedusing the extension layer in the communication. The attributeinformation may indicate that, although a frame rate is 60 fps only forthe broadcasting data as a use case, the frame rate can be improved upto 120 fps when the communication data is combined. The attributeinformation may indicate that backup data of the broadcasting istransmitted through the communication. Thus, in the case that areception status is degraded due to rain attenuation, the transmissionside can switch the transmission using the attribute information so asto transmit the data through the communication.

The attribute information may indicate information identifying the codedstreams correlated with each other. For example, the attributeinformation can indicate the PID of the TS packet in which the data ofthe basic layer transmitted through the broadcasting is stored, and thesegment in the DASH data transmitted through the communication, or theidentification information on the video data such as the track ID in theMP4.

The attribute information may indicate information indicating thebroadcasting-side data and communication-side data, which are to besynchronously played back. Thus, the transmission side can transmitvideo images of a plurality of viewpoints or video images of a mainscreen and a sub-screen in picture-in-picture through the broadcastingand the communication, respectively.

3) Information indicating whether the audio or video transmitted throughthe broadcasting and the audio or video transmitted through thecommunication are to be synchronously played back may be included as theattribute information.

4) Information indicating whether audio or video clock informationtransmitted through the broadcasting is identical to audio or videoclock information transmitted through the communication may be includedas the attribute information.

5) Information indicating that whether the communication-side data islive content may be included in the attribute information.

For example, unless the transmitted content is the live content, thedata after current clock time (T1) can be acquired. Accordingly, thebroadcasting-side data can be played back without delay by starting thedata reception from data which can be played back at clock time (T2)obtained by adding a time until the reception start since a contentacquisition request (or an estimated value of the time) and a summation(ΔT) of a data buffering time to the current clock time. At this point,the communication-side data is played back from clock time T2. On theother hand, in the case that the transmitted content is live content,the broadcasting-side data is buffered for ΔT, the playback of both thebroadcasting data and the communication data may be started at clocktime T2.

In the case that the communication side multicasts or broadcasts thecontent by the RTP, the data after the current clock time cannot beacquired irrespective of whether the content is the live content.Accordingly, information indicating whether the communication-side datais multicast or broadcast may be included in the attribute information.

[Reception Device]

A configuration example of the reception device in the case that thedata is received through the broadcasting using the TS while the data isreceived through the communication using the DASH or RTP (Real-timeTransport Protocol) will be described below.

FIG. 8 is a block diagram illustrating a configuration example of thereception device of the first modification of the first exemplaryembodiment. FIG. 8 illustrates the configuration example of thereception device that performs the reception method in FIG. 7B.

Reception device 300 in FIG. 8 includes identification informationacquisition part 301, decision part 302, communication combination-usedetermination part 303, Loc information acquisition part 304,broadcasting receiver 305, and communication receiver 306. Theconfiguration of the reception device that performs the reception methodin FIG. 7A corresponds to the case that Loc information acquisition part304 is eliminated from the configuration in FIG. 8.

Identification information acquisition part 301 has a function ofperforming Step S301 in FIG. 7B. Specifically, identificationinformation acquisition part 301 acquires the service informationtransmitted through the transmission channel constituting the entrypoint, and acquires the transmission channel identification descriptor(auxiliary information) included in the service information.Identification information acquisition part 301 interprets theinformation on the transmission channel identification descriptor.

Decision part 302 has a function of performing Step S302 in FIG. 7B, anddecides the data to be received based on the playback capability of theterminal or the availability of the communication channel.

Communication combination-use determination part 303 has a function ofperforming Step S303 in FIG. 7B, and decides (determines) whether thedata transmitted through the communication is to be received.

Loc information acquisition part 304 has a function of performing StepS304 in FIG. 7B, and acquires the location data of thecommunication-side data.

(Second Modification)

An example of the reception method in the case that the attributeinformation or the location information is stored in the programinformation on the broadcasting will be described in a secondmodification.

[Reception Method]

FIG. 9 is a flowchart illustrating an operation example on the receptionside in the broadcasting and communication cooperation service of thesecond modification of the first exemplary embodiment. FIG. 9illustrates the operation example in which the reception devicedetermines whether the broadcasting content and the communicationcontent are to be synchronously played back and plays back thebroadcasting content and the communication content in the case that theattribute information or the location information is stored in theprogram information on the broadcasting.

The operation in FIG. 9 is based on the operation in FIG. 7A. However,in the operation in FIG. 9, the transmission data is not the MMT assetbut more general content.

The program information transmitted through the transmission channelconstituting the entry point is acquired, the transmission channelidentification descriptor included in the program information isacquired, and the attribute information on the content or the locationinformation on the communication content is acquired (Step S401).

In the case that the entity of the location information is not stored inthe program information, the data entity of the location information isacquired by the method similar to that in FIG. 7B.

The data to be received is decided based on the playback capability ofthe reception device or the availability of the communication channel(Step S402).

Whether the communication content is to be acquired is decided (StepS403). When the communication content is to be acquired (YES in S403),the flow goes to Step S404, and the data is received through both thetransmission channels of the broadcasting and communication. When thecommunication content is not to be acquired (NO in S403), the flow goesto Step S409, and the data is received only through the broadcasting. InStep S410, only the broadcasting content is played back.

Whether the broadcasting content and the communication content are to besynchronously played back is determined (Step S405).

When the broadcasting content and the communication content are to besynchronously played back (YES in S405), the reference clocks of thebroadcasting content and communication content are synchronized witheach other in Step S406, and the broadcasting content and thecommunication content are synchronously played back in Step S407.

The reference clock synchronization in S406 may be performed in advanceof the reception in S404. The reason is as follows. In the case that theplayback of the reception data of the content is started afterpre-buffering, sometimes the reception data is decoded and played backafter confirmation of the reception of the data in which the PTS is T1in the broadcasting content and the data in which the PTS is T1 in thecommunication content (at this point, it is assumed that the PTSs of thebroadcasting content and communication content are already synchronizedwith each other). In determining whether the synchronously played backpieces of data are prepared, it is necessary that the reference clocksof the broadcasting content and communication content are alreadysynchronized with each other.

The reference clock synchronization in S406 can be made based on eitherreference clock used in the broadcasting or communication. For example,in the case that the PCR (Program Clock Reference) is used in thebroadcasting while the NTP (Network Time Protocol) is used in thecommunication, the reference clocks of the broadcasting content andcommunication content can be synchronized with each other by convertingthe NTP-based audio or video DTS or PTS into the PCR-based audio orvideo DTS or PTS. The DTSs or PTSs of the broadcasting and communicationmay be converted so as to be synchronized with an inherent clock used inthe reception device.

The attribute information includes information indicating whether thepieces of reference clock information on the plurality of components areidentical to each other, and the reception side can recognize that thepieces of the reference clock information differ based on the attributeinformation. In such cases, the reference clocks of the broadcastingcontent and communication content can be synchronized with each other bythe above method.

In the operation of FIG. 9, the attribute information or the locationinformation is transmitted while stored in the program information onthe broadcasting. When the necessity of the synchronization playback iseliminated, the transmission channel identification descriptor in whichthe pieces of information are described does not need to be stored inthe program information on the broadcasting.

The attribute information or the location information is stored in theprogram information on the broadcasting described in the secondmodification. Alternatively, in the case that the program informationincludes the transmission channel identification descriptor, thereception device may synchronously play back the stream in which thelocation information is described in the transmission channelidentification descriptor and the broadcasting stream. At this point,the transmission channel identification descriptor does not need toinclude the attribute information indicating whether the streamstransmitted through the broadcasting and the communication are to besynchronously played back.

In other words, the reception method of the second modification mayinclude: the reception step of receiving the content transmitted usingthe broadcast wave and the content transmitted using the communicationchannel; and the playback step of playing back the content transmittedusing the broadcast wave and the content transmitted using thecommunication channel while synchronizing the pieces of content, whenthe auxiliary information for synchronizing the content transmittedusing the broadcast wave and the content transmitted using thecommunication channel is received.

[Reception Device]

FIG. 10 is a block diagram illustrating a configuration example of thereception device of the second modification of the first exemplaryembodiment. FIG. 10 illustrates the configuration example of thereception device that performs the reception method in FIG. 9.

Reception device 400 in FIG. 10 includes identification informationacquisition part 401, decision part 402, communication combination-usedetermination part 403, Loc information acquisition part 404,broadcasting receiver 405, communication receiver 406, synchronizationdetermination part 407, and player 408.

Because identification information acquisition part 401 to communicationreception part 406 are similar to identification information acquisitionpart 301 to communication reception part 306 in FIG. 8, the descriptionis omitted.

Synchronization determination part 407 has a function of performing theprocessing in Step S405 of FIG. 9.

Player 408 decodes and plays back the broadcasting content or thecommunication content by the playback method decided based ondetermination results of communication combination-use determinationpart 403 and synchronization determination part 407.

(Third Modification)

Other examples different from those of the first and secondmodifications will be described below as a third modification.

[Others 1]

The transmission channel is not limited to the combination of thebroadcasting and the communication, but the transmission channel may bea combination of the identical transmission channels such as thebroadcasting and broadcasting and the communication and communication.

In the case that the information in the package unit is not indicatedlike the transmission channel identification descriptor, whether eachasset is to be transmitted through the broadcasting or the communicationor whether the asset transmitted through the communication exists in thepackage may be decided by interpreting the location information on eachasset in FIGS. 1A and 1B.

(Location Information)

The location information may include the URL information on theacquisition destination of the asset. In the case that the acquisitiondestination is the URL, whether the asset is to be transmitted throughthe broadcasting or the communication can be decided based on whetherthe URL is the specific URL previously defined in the broadcastingservice.

For example, in the case that the broadcasting asset is transmitted inthe same stream as that of the message information on the MPT, the ID(for the MMT packet, packet_id) of the packet in which the asset data isstored is indicated as the acquisition destination of the broadcastingasset in the location information, and the URL is indicated as theacquisition destination for the asset transmitted through thecommunication. Accordingly, in the location information, whether theasset is to be transmitted through the communication may be decidedbased on whether the acquisition destination is the URL.

(Modification of Description of MPT)

In FIGS. 1A and 1B, the location information on each asset and theindividual transmission channel identification descriptor are defined asthe information on each asset. Alternatively, a field indicating anasset coding system may separately be provided. The coding system isinformation necessary for the decoding, and desirably the coding systemis signaled in the information, such as the MPT, which can be acquiredin advance of the decoding. For example, the information such asstream_type in the MPEG-2 system can be used.

For the coding system in which the scalable coding can be performed,whether the asset is the basic layer or the extension layer may beindicated together with the coding system.

The plurality of assets having the scalability are sometimes included inthe identical MMT package as in a case that two pieces of video havingthe time scalability exist in the identical MMT package. At this point,information indicating that the asset in the extension layer correspondsto the asset in which basic layer may be indicated. For example, theasset ID of the asset in the corresponding basic layer may be indicatedwith respect to the asset in the extension layer. The assets in theextension layer and basic layer may be grouped, and a group ID may beallocated to each asset.

These pieces of information can be indicated in the program informationon the broadcasting even in the case that the TS is used in thebroadcasting while the DASH or RTP is used in the communication. Forexample, the dependence relationship (for example, thecommunication-side video stream corresponds to the extension layer)between the video stream transmitted through the broadcasting and thevideo stream transmitted through the communication or informationindicating the communication-side audio or video coding system can bedescribed in the PMT descriptor and the like. Whether thebroadcasting-side stream and the communication-side stream are to besynchronously played back may be indicated.

(Information on Transmission Channel)

The information indicating whether the content data is to be transmittedonly through the broadcasting or whether the content data is to betransmitted by the combination of the broadcasting and the communicationmay be stored in broadcasting program information such as the EPG.

For example, in the case that the data transmitted through thecommunication cannot be played back or recorded as in the case that thereception device is not connected to the communication network or thatthe reception device is not compatible with the data acquisition throughthe communication, message information indicating that the data cannotbe played back or recorded may be displayed when viewing selection orrecording reservation is performed from the EPG.

Information indicating whether the data transmitted through thecommunication can be acquired in advance of a broadcasting program startclock time may be stored. In particular, in a download type system suchas the DASH, the communication-side data is downloaded in advance of thebroadcasting program start, which allows the playback of both thebroadcasting data and the communication data to be started at thebroadcasting program start clock time.

For example, in the case that the communication-side data can beacquired in advance of the broadcasting program start clock time, thereception device may start the reception of the communication-side databefore the broadcasting program start clock time. At this point, thereception start clock time can be fixed such that a predeterminedbuffering data amount or the data corresponding to the buffering timecan be received at the broadcasting program start clock time.

For example, the similar operation may be performed in the broadcastingprogram recording reservation.

In the broadcasting, because a user can select the plurality ofbroadcasting programs at any time, even if the communication data of thebroadcasting program next to the currently viewing channel is previouslyreceived, an advantage of previously receiving the communication data iseliminated when the viewing broadcasting program is switched. Therefore,the communication-side data may previously be buffered at a certainviewing clock time with respect to all the broadcasting programs whichcan be viewed after the certain viewing clock time and data of which istransmitted by the combination of the broadcasting and thecommunication. In the case that the pieces of data of all thebroadcasting programs cannot be received, the broadcasting program maybe selected and received within a receivable range.

The information indicating whether the broadcasting-side data and thecommunication-side data are to be synchronously played back may beincluded in the broadcasting program information such as the EPG, andthe communication-side data may previously be buffered when thebroadcasting-side data and the communication-side data are to besynchronously played back. When the broadcasting-side data and thecommunication-side data are not to be synchronously played back, thereception of the communication-side data may be started after thereception of the broadcasting-side data is started.

Even in the case that the EPG does not include such pieces ofinformation, a similar message can be displayed by acquiring the similarinformation through analysis of the MPT in the MMT or the PMT during theuse of the TS in the broadcasting.

The pieces of information may be stored in control information, such asa TMCC signal in the broadcasting system (ISDB-T) of Japan, which isused to decode the signal transmitted through the transmission channel.

Thus, the necessity of the reception through the communication can bedetermined during the decoding, and the start on the communication sidecan be advanced.

(Format)

The HTTP-based file format is not limited to the DASH, but theHTTP-based file format may be HLS (HTTP Live Streaming) or MSS(Microsoft Smooth Streaming). The content management informationcorresponding to the MPD also exists in the HLS or MSS, so that therelationship between the broadcasting-side data and thecommunication-side data can be indicated by the mechanism similar tothat of the DASH.

On the communication side, the TS stream may be used, or the format inwhich the field indicating the time stamp is added to the leading fourbytes of the TS packet may be used. The time stamp-added TS is used invarious standards such as BD (Blu-ray (registered trademark) Disc) andIPTV forum.

[Others 2]

(Attribute Information and Location Information)

In the attribute information or the location information, the attributeof the whole content and the individual attribute of the audio or videostream may separately be stored.

For example, in the case that the DASH is used on the communicationside, the attribute information on the whole content indicating that thebroadcasting content and the communication content are to besynchronously played back or that the broadcasting content is thescalability basic layer while the communication content is the extensionlayer may be stored in the transmission channel identificationdescriptor or the like. On the other hand, the individual attribute ofeach stream such as the information identifying the audio or video ofthe synchronization playback target may be stored in the MPD.

As to an example of the individual attribute of each stream, in the casethat the video in the broadcasting is correlated with sub-voice audiotransmitted through the communication, the PID of the TS packet in whichthe video is stored and an audio track or segment in the DASH data suchas an audio track ID or information identifying Adaptation Set orRepresentation may be correlated with each other in the MPD. At thispoint, the identification information on the broadcasting-side media mayinclude an ID of the transport stream including the TS packet of the PIDand a service ID in addition to the PID.

The content of the MPD is sometimes updated, and a distribution serverof the DASH content manages the update information. Therefore,particularly the individual attribute of the stream is described in theMPD, which allows establishment of a balance between an advantage ofreducing information exchange between a broadcasting contenttransmission device and a communication content transmission server andan advantage of rapidly starting the communication content receptionstart processing by storing the whole attribute in the information, suchas the PMT, which is acquired during the broadcasting reception start.

The whole attribute and the individual attribute may be described inboth or one of the descriptor such as the PMT in the broadcasting andthe MPD. For example, in the broadcasting, the whole attribute and theindividual attribute may be described in the descriptor of theapplication control information such as the AIT.

(Attribute Information)

Information indicating whether the pieces of clock information on thestreams transmitted through the different transmission channels such asthe broadcasting and the communication are synchronized with each otheror a method for synchronizing the pieces of clock information on thestreams may be included in the attribute information. In this case, thereception device may perform the clock synchronization based on theinformation.

For example, information identifying the following three methods may bedescribed as the attribute information.

Method 1) The streams being the synchronization targets are based on acommon clock, and the necessity of the clock synchronization between thestreams is eliminated.

Method 2) Like the descriptor in the PMT, the synchronization isperformed based on clock synchronizing information that is transmittedseparately from the stream.

Method 3) Like TS timeline extension (13818-1: 2013/AMD6 (2nd WD)) thatis currently standardized in MPEG, the synchronization is performed byreferring to the independent stream including the information for theclock synchronization.

In method 3, the attribute information may include the PID of the TSpacket in which the clock synchronizing stream is stored.

(Fourth Modification)

For example, in FIGS. 6A to 7B, the method for storing the locationinformation and the like are described in the case that the data istransmitted using TS in the broadcasting while the data is transmittedusing the DASH or RTP in the communication.

A specific example of the location information storage method will bedescribed in a fourth modification.

FIG. 11 is a view illustrating an example of a data structure of serviceinformation in the broadcasting and communication cooperation service ofthe fourth modification of the first exemplary embodiment. FIG. 11illustrates an example of a descriptor (location information descriptor)indicating the location information on the MPD or the like. The locationinformation may be included in the transmission channel identificationdescriptor. Therefore, it may be considered that the locationinformation descriptor corresponds to the transmission channelidentification descriptor.

In the fourth modification, the descriptor is stored in the PMT orsection data different from the PMT.

A transmission format indicating the type of the data entity referred toby the location information, the location information, and a fieldindicating synchronization information between the PCR in thebroadcasting and the communication-side data are included in theinformation indicated by the descriptor.

It is assumed that the location information of the fourth modificationindicates a reference destination of the data entity of the locationinformation. The case that the data entity of the location informationis the MPD is described by way of example, the MPD is indicated as thetransmission format, and the synchronization information between the PCRand the NTP is indicated as the synchronization information.

Because the MPD is the location information used in the DASH, the DASHmay be indicated as the transmission format, and the referencedestination of the MPD may be indicated as the location. The field ofthe transmission format does not need to be included in the case thatthe transmission format can be identified by an extension in the URL ofthe location information. The MPD has the two ways of the case that theMPD is transmitted through the broadcasting and the case that the MPD istransmitted through the communication network. An MPEG-2 TS privatesection or the like is used in the case that the MPD is transmittedthrough the broadcasting. Accordingly, the identification information onthe TS packet, such as the PID of the private section, in which the MPDis stored in the transport stream can be indicated as the locationinformation on the MPD in the case that the MPD is transmitted throughthe broadcasting, and the information on the URL or the like can beindicated as the location information on the MPD in the case that theMPD is transmitted through the communication network.

[Reception Method]

An operation example of the reception device in the case that thedescriptor indicating the location information is analyzed tosynchronously play back the broadcasting content and the communicationcontent will be described below as a reception method of the fourthmodification.

FIG. 12 is a flowchart illustrating an operation example on thereception side in the broadcasting and communication cooperation serviceof the fourth modification of the first exemplary embodiment.

In Step S801, the location information descriptor stored in the PMT isanalyzed.

In Step S802, whether the MPD exists in the broadcasting is determined.When the MPD exists in the broadcasting (the MPD is transmitted throughthe broadcasting) (YES in S802), the flow goes to Step S803, and thedata entity of the MPD is acquired from the TS packet having the PIDindicated by the location information. On the other hand, when the MPDdoes not exist in the broadcasting (NO in S802), the MPD is acquiredfrom the communication server based on the URL indicated by the locationinformation and the like.

In Step S805, based on an analysis result of the MPD, the data acquiredfrom the DASH content is decided, and acquired by download (orprogressive download).

In Step S806, the broadcasting content and the communication content aresynchronously played back based on the synchronization informationincluded in the location information descriptor or the synchronizationinformation, which is acquired from the TS packet in which timelineextension information is stored in the case that the MPEG-2 TS timelineextension is used.

In the case that the timeline extension is used, the synchronizationinformation does not need to be included in the location informationdescriptor. In the case that the DASH content and the broadcastingcontent need not to be synchronously played back, the synchronizationinformation does not need to be transmitted. In this case, whether thepieces of content need to be synchronously played back may be determinedbased on the synchronization information on the location informationdescriptor or whether the synchronization information in the timelineextending data exists. Whether the synchronization playback needs to beperformed may separately be indicated.

When the synchronization playback does not need to be performed, thestart and stop of the playback of the DASH content can be decided basedon a user instruction or a control command in a hybridcast applicationin Step S806. In this case, it is assumed that whether the data is to beacquired through the communication is decided in a preceding step ofS801.

In FIG. 12, by way of example, the MPD is acquired to play back the DASHcontent. The same holds true for the case that the data of other systemsuch as the RTP and the TS are acquired and played back.

In the timeline extension, an access unit in which the timelineextension information is stored is defined, and both the descriptorindicating the location information and the descriptor indicating thesynchronization information can be stored in the access unit.

Accordingly, without the transmission of the location informationdescriptor, the location information and the synchronization informationmay be indicated by the timeline extension. Because the PID cannot beindicated as the location information in the current timeline extension,the PID can be signaled by extending a field indicating a scheme type ofthe location information.

An upper limit of a section size of the PMT is restricted to 1021 bytes,and sometimes the section size of the PMT exceeds the upper limitdepending on the URL in the location information. Although the PMTsection can be divided and stored, desirably the PMT is particularlystored in one section.

Accordingly, in the case that the section size of the PMT exceeds 1021bytes, the location information descriptor may be transmitted by asection different from the PMT. In the case that the locationinformation indicates the PID, the location information can fall withinthe upper limit of the section size of the PMT, and the locationinformation can be included in the PMT. Therefore, the section in whichthe location information is stored may be changed based on whether thelocation information is the PID or the URL.

(Fifth Modification)

In the description of the fourth modification, the location informationcan be indicated even in the TEMI (Timeline and Extend Media Informationstream) access unit of the timeline extension.

Specifically, the URL of the communication-side content and the like canbe described using temi_location_descriptor. Intemi_location_descriptor, the URLs of the plurality of pieces of contentcan be described, and flexible operation can be performed with respectto the description of the URL because the restriction of the data sizedoes not exist unlike the section size of the PMT.

In the case that the PID of the TS packet in the transport stream isindicated as the location information, the location information has thesmall data size, and the location information is acquired during theanalysis of the PMT by referring to the location information descriptor,which allows the reduction of the delay time relevant to theacquisition. Therefore, desirably both the location informationdescriptor and temi_location_descriptor in the TEMI access unit can beused as a storage site of the location information.

An example of a syntax (data structure) of the location informationdescriptor according to a fifth modification will be described below.

FIG. 13A is a view illustrating a syntax example of the locationinformation descriptor of the fifth modification of the first exemplaryembodiment. FIG. 13A illustrates a syntax example of the locationinformation descriptor that is used to store the location information inone of the location information descriptor and the TEMI access unit.

In the description of the fifth modification, it is assumed that theinformation on the synchronization with the PCR is not included in thelocation information descriptor, but described usingtemi_timeline_descriptor of the TEMI access unit. Semantics of eachfield in FIG. 13A will be described.

“data_format” is similar to the transmission format in FIG. 11. That is,“data_format” indicates the format of the meta-information on theplayback control used in the service, such as the MPD in the DASH, theplayback control meta-file in VOD (Video On Demand) specifications ofthe IPTV forum, and TTS (Time-stamp TS) defined by the IPTV forum.“data_format” may indicate not the meta-information such as the TTS, theMP4 file, and the AV coded data, but the identification information suchas the stream. “data_format” may indicate the MPT in the MMT, the PAmessage, the MMT packet, or the asset.

For example, the time scalability can be implemented in the video codingsystem such as H.265. It is assumed that the basic layer is transmittedat the frame rate of 60 fps through the broadcasting, and that the codeddata of the extension layer is transmitted in order to improve the framerate from 60 fps to 120 fps through the communication. In this case,only the URL of the coded stream in the extension layer needs to beindicated as the location information on the communication content. Theinformation such as the resolution and the coding system in the codedstream can be acquired in the broadcasting data in which the basic layeris transmitted.

“location_type” is used to identify whether the location information isindicated by the PID of the TS in the broadcasting or the URL in thecommunication. It is assumed that “location_type” indicates the PID ofthe TS in the broadcasting for location_type=0. For example, thelocation information descriptor can be used outside the TS like the MMT(MPEG Media Transport) of the MPEG. “location_type” does not need to beused in the format other than the TS. For example, another piece ofinformation such as packet_id of the MMT packet in the MMT may be usedin order to identify the location.

“PID” indicates a PID of the TS packet. In the case that thebroadcasting is constructed with the plurality of transport streams, theidentification number of the transport stream and the like may also bestored.

“url_location” indicates which one of the location informationdescriptor and the TEMI access unit stores the URL of the communicationcontent therein. In the fifth modification, it is assumed that the URLof the communication content is stored in the location informationdescriptor for url_location=0. It is also assumed that the URL of thecommunication content is stored in temi_location_descriptor of the TEMIaccess unit for url_location=1.

“url_length” indicates a byte length of “url_path”. “url_path” indicatesURL data.

FIG. 13B is a view illustrating a syntax example of the locationinformation descriptor of the fifth modification of the first exemplaryembodiment. FIG. 13B illustrates another syntax example different fromthe syntax of the location information descriptor in FIG. 13A. Thesyntax in FIG. 13B differs from the syntax in FIG. 13A in thatdata_format field does not exist in the case that the locationinformation is stored in the TEMI access unit.

At this point, temi_location_descriptor can indicate a TEMI service typein a field called service_type. The service type corresponds todata_format. Accordingly, it is assumed that the information ondata_format is indicated in service_type field.

Sometimes both data_format field and service_type oftemi_location_descriptor exist in the syntax of FIG. 13A. In this case,it is assumed that data_format field and service_type oftemi_location_descriptor indicate the identical information.

In temi_location_descriptor, only the URL of the communication contentcan be indicated without signaling service_type. Accordingly, in thecase that the syntax in FIG. 13A is used, data_format of the locationinformation descriptor is referred to as the transmission format, andservice_type of temi_location_descriptor does not need to be signaled.

FIG. 13C is a view illustrating a syntax example of the locationinformation descriptor of the fifth modification of the first exemplaryembodiment. FIG. 13C illustrates still another syntax example differentfrom the syntax of the location information descriptors in FIGS. 13A and13B.

The syntax in FIG. 13C differs from the syntax in FIG. 13A in thatconditional branching of url_location is performed at the beginning.That is, in the case that the location information exists in thelocation information descriptor for url_location=0, the PID of the TS inthe broadcasting or the communication URL is stored according tolocation_type. On the other hand, for url_location=1, location_type isnot described in the location information descriptor, but location_typeis indicated in the service_type field of temi_location_descriptor inthe TEMI access unit, and the PID of the TS in the broadcasting or thecommunication URL is stored in temi_location_descriptor.

FIG. 13D is a view illustrating a syntax example of the locationinformation descriptor of the fourth modification of the first exemplaryembodiment. FIG. 13D illustrates yet another syntax example differentfrom the syntax of the location information descriptors in FIGS. 13A to13C.

The syntax in FIG. 13D differs from the syntax in FIG. 13A in thaturl_location and location_type are integrated. The syntax in FIG. 13Dindicates the broadcasting PID for location_type=0, and indicates thecommunication URL for location_type=1. The case of location_type=2indicates that the PID of the TS in the broadcasting or thecommunication URL is stored in temi_location_descriptor of the TEMIaccess unit.

The data or data structure of the syntax of the location informationdescriptor is not limited to the above examples. For example, acombination with another piece of data may be used by integrating thelocation type and the format type. For example, the field of thetransmission format does not need to be included in the case that thetransmission format can be identified by an extension in the URL of thelocation information. For example, when the location informationdescriptor does not exist, the location information is indicated bytemi_location_descriptor, and the url_location field may be eliminated.

(Sixth Modification)

Another example different from the location information of the fifthmodification will be described below.

(Another Example of Location Information)

For example, sometimes the plurality of TEMI streams are included ineach kind of the timeline in the case that a plurality of timelines ofat least two kinds exist in the identical program.

In this case, the plurality of pieces of location information may bestored in the location information descriptor. In the case that theplurality of pieces of location information are stored, loops as many asthe number of TEMI streams are produced in the location informationdescriptor, and the location information corresponding to each TEMIstream is stored. As a method for indicating the correlation between theplurality of location information loops and the plurality of TEMIstreams in the location information descriptor, for example, acorrelation may be indicated by the correspondence between the order ofthe loop of the location information and the order of an ES loop (PMTsecond loop) indicating the TEMI stream. In the case that at least twokinds of timelines exist, the location information may be stored not inthe location information descriptor but in temi_location_descriptor ofthe TEMI access unit, or the location information descriptor may bestored in the ES loop (PMT second loop).

(Update of Location Information)

Desirably the update of the content of the location information such asthe meta-information can be dealt with.

For example, a reload flag is added to the location informationdescriptor in the PMT, the reload flag is set to 1 in the case that thecontent of the location information is to be updated, and the receptiondevice may determine that the content of the location information isupdated for reload=1, and reacquire the PID or URL stored in thelocation information. In the case that the location information on thePID or URL is not updated while only the data is updated, only the datamay be reacquired.

Information indicating whether the content of the location informationor the data such as the MPD the acquisition destination of which isindicated by the location information is updated may independently beindicated.

The location information descriptor in the periodically-transmitted PMTmay sequentially be checked. Alternatively, since the sequentialchecking processing is heavy, the section data to store the locationinformation descriptor and the like or the event section for making anotification of the update may separately be generated, and periodicallybe transmitted.

In the reception device, whether the location information is updated canbe determined when the version number is confirmed in the section. Inthe case that the location information is transmitted by thebroadcasting section, the update of the meta-information is indicated byupdating the version number of the section of the location information.

After the acquisition of the communication-side data is started based onthe location information acquired from the broadcasting, the updatecontent of the location information may be acquired through thecommunication.

[Reception Method]

An operation example of the reception device in the case that thedescriptor indicating the location information is analyzed tosynchronously play back the broadcasting content and the communicationcontent will be described below as a reception method of the sixthmodification.

FIG. 14 is a flowchart illustrating an operation example on thereception side in the broadcasting and communication cooperation serviceof the sixth modification of the first exemplary embodiment.

Step S804 in FIG. 12 is changed to Steps S906, S907, and S908 in FIG.14. Because other operations (Steps S901 to S905) are similar to theoperations in FIG. 12 (Steps S801 to S803, Steps S805, and S806), thedescription is omitted.

Which one of the location information descriptor and the TEMI accessunit stores the URL of the acquisition destination of the MPD therein isdetermined in Step S906. When the URL exists in the location informationdescriptor (YES in S906), the flow goes to Step S907, the locationinformation descriptor is analyzed, and the MPD is acquired from thecommunication server based on the URL indicated by the locationinformation. On the other hand, when the URL exists in the TEMI accessunit (NO in S906), the MPD is acquired from the communication serverbased on the URL indicated by temi_location_descriptor of the TEMIaccess unit.

FIG. 14 illustrates the case that the MPD is indicated as the formatinformation by way of example. However, even in the case of anotherpiece of meta-information, the broadcasting content and thecommunication content can be synchronously played back by the flow ofoperation similar to that in FIG. 14.

FIG. 15 is a flowchart illustrating another operation example on thereception side in the broadcasting and communication cooperation serviceof the sixth modification of the first exemplary embodiment. FIG. 15illustrates operation in the case that the format information is anotherpiece of meta-information other than the MPD. More specifically, FIG. 15illustrates the operation to acquire the URL of the data entity of thestream instead of the URL of the meta-information in Step S907 or S908of FIG. 14 in the case that not the meta-information such as the MPD butthe format of the data entity of the stream is indicated in the formatinformation.

In Step S1001, the reception device analyzes the location informationdescriptor.

Whether the data indicated by the format exists in the broadcasting isdetermined (Step S1002). When the data exists in the broadcasting (YESin S1002), the flow goes to Step S1003, and the PID indicated by thelocation information is acquired. At this point, because it is notconsidered that the data entity such as the stream is included in thebroadcasting, the format is decided to be meta-data when the data existsin the broadcasting.

The meta-information file is acquired from broadcasting stream based onthe PID (Step S1004), and the communication data to be acquired isdecided (Step S1005).

On the other hand, when the data exists in the communication (NO inS1002), the flow goes to Step S1008, and whether the URL of thecommunication data exists in the location information descriptor ortemi_location_descriptor of the TEMI access unit. The URL is acquired inStep S1009 or S1010 depending on each case.

Whether the format is the meta-information is determined in Step S1011.When the format is the meta-information (YES in S1011), the flow goes toStep S1012, the meta-information is acquired from the communicationstream based on the URL. Then the flow goes to Step S1005, and thecommunication data to be acquired is decided.

After the communication data to be acquired is decided in Step S1005, orwhen the format is determined to be not the meta-information in StepS1011, the flow goes to Step S1006, and the communication data isacquired.

Finally, in Step S1007, the broadcasting content and the communicationcontent are synchronously played back based on the synchronizationinformation included in the location information descriptor or thesynchronization information indicated by the MPEG-2 TS timelineextension.

(Seventh Modification)

In the above description, whether the broadcasting content and thecommunication content are to be synchronously played back is determined,and the broadcasting content and the communication content are acquiredand synchronously played back when the broadcasting content and thecommunication content are to be synchronously played back.

On the other hand, in the description of a seventh modification,information indicating whether the audio or video reference clockinformation transmitted through the broadcasting is identical to theaudio or video reference clock information transmitted through thecommunication is included in the service information (such as thetransmission identification descriptor), and the operation is performedbased on the information.

[Information Indicating Whether Reference Clocks (Timelines) ofBroadcasting and Communication are Synchronized with Each Other]

In the case that the broadcasting content and the communication contentare transmitted using the MMT, the DASH, the RTP, or the hybridcast, theinformation indicating whether the audio or video reference clockinformation transmitted through the broadcasting is identical to theaudio or video reference clock information transmitted through thecommunication may be stored in the transmission identificationdescriptor, the program information, the EPG, or the EIT.

For example, in the case that the content transmitted through thebroadcasting and the content transmitted through the communication areoperated based on a common reference clock (such as the provision of thetime stamp), information indicating that the pieces of contenttransmitted through the broadcasting and communication are operatedbased on the common reference clock is stored. In the case that thecontent transmitted through the broadcasting and the content transmittedthrough the communication are operated based on different referenceclocks, information indicating that the pieces of content transmittedthrough the broadcasting and communication are operated based on thedifferent reference clocks is stored.

Only in the case that different pieces of reference clock informationare used in the broadcasting and communication, information (such astimeline extension information) necessary for the reference clocksynchronization may be indicated. A storage site or a kind of theinformation necessary for the reference clock synchronization and areference clock synchronization method may be indicated.

The reference clock synchronization can be made based on eitherreference clock used in the broadcasting or communication.

For example, in the case that the PCR (Program Clock Reference) is usedin the broadcasting while the NTP (Network Time Protocol) is used in thecommunication, the kind or method of the reference clock synchronizationmay be indicated by, for example, an indication that the referenceclocks of the broadcasting content and communication content can besynchronized with each other by converting the NTP-based audio or videoDTS or PTS into the PCR-based audio or video DTS or PTS. The kind ormethod of the reference clock synchronization may be indicated by, forexample, an indication that the DTSs or PTSs of the broadcasting andcommunication are converted so as to be synchronized with the inherentclock used in the reception device.

The identification information indicating the kind or method of theinformation necessary for the reference clock synchronization may beanalyzed to perform the reference clock synchronization by the methodbased on the identification information.

In the case that the plurality of streams have different referenceclocks, information indicating that the plurality of streams havedifferent reference clocks may be stored in the descriptor. Thedescriptor may be indicated in each of the different reference clocks,or the different reference clocks may be indicated by one descriptor.Information indicating the correlation between the reference clock andthe program in which the reference clock is used may be stored.

Information indicating whether the reference clocks are identical toeach other may be indicated as the above descriptor, or anotherdescriptor, a table, or a section may be used as the information.Information indicating whether the reference clocks are identical toeach other may be indicated based on whether the information (such asthe timeline extension information) necessary for the clocksynchronization exists. The difference of the clock information can beindicated by the fact that the information necessary for the clocksynchronization exists. Alternatively, the difference of the clockinformation may be indicated using the communication content attributeinformation (such as information on the format or kind and an extensiondescribed in the location information or URL) described in thetransmission identification descriptor.

For the hybridcast, the difference of the clock information may bestored in an AIT-controlled section or an application.

The reception device synchronizes the broadcasting reference clockinformation and the communication reference clock information whendetermining that different pieces of clock information are used. Whendetermining that the common clock information is used, the receptiondevice decides that the clock synchronization is unnecessary. Forexample, the reception device may synchronize the reference clock of thecontent transmitted using the communication channel with the referenceclock of the content transmitted using the broadcast wave based on thedifference information when the reception device receives the auxiliaryinformation including the difference information between the referenceclock of the content transmitted using the broadcast wave and thereference clock of the content transmitted using the communicationchannel, and the reference clock of the content transmitted using thebroadcast wave differs from the reference clock of the contenttransmitted using the communication channel.

The reception device may determine whether the reference clocks of thebroadcasting content and communication content are actually to besynchronized with each other in consideration of all the pieces ofinformation such as the user selection or user setting through a userinterface, a content provider or a service provider, an intention of abroadcasting station, specifications of the reception device, and anintention of a receiver manufacturer in addition to the identificationresult that is stored in transmission identification descriptor toindicate whether the pieces of reference clock information on the dataare identical to each other.

When determining that the reference clock synchronization is to beperformed, the timing at which the reception device actually starts thesynchronization may be after the determination, or at the time beforethe determination when the information on the synchronization isacquired. Alternatively, the synchronization may be performed accordingto the time the acquisition of the communication content is started (forexample, a given time before the acquisition of the content is started,or the same time as the start of the acquisition).

In the case that the playback of the clock of the reference clock (forexample, broadcasting PCR) being the reference source is not completed(for example, the clock cannot be used because an influence of jitterhas not been smoothed yet), the clock synchronization with the referencedestination may be started at the time the playback of the clock of thereference clock information on the reference source is completed.

In the case that the information indicating whether the broadcastingreference clock and the communication reference clock are synchronizedwith each other is indicated by the EPG, similarly to pro-buffering ofthe communication content, whether the synchronization of the referenceclock is required or the synchronization of the reference clock may bestarted before the start of the broadcasting. Thus, the service canearlier be provided to the viewer by performing the synchronization ofthe reference clock as soon as possible.

The information indicating whether the reference clocks are identical toeach other can be applied not only the combination of the broadcastingand the communication but other cases as long as the different pieces ofreference clock information are used in the data acquired through theidentical channel or the plurality of channels such as the broadcasting,the communication, and the accumulation format.

A part of or all the functions or pieces of processing described in theseventh modification may be mounted by hardware or software. Thefunctions or pieces of processing described in the seventh modificationcan partially be mounted by hardware or software.

For example, in the case that the functions or pieces of processing aremounted by software, instructions of the functions or pieces ofprocessing described in the seventh modification may be issued, PUSH maynotify the state of the reception function, or the functions acquired byPULL may be packaged and provided as an API function.

The API function can be performed from an application. In the case thatthe functions or pieces of processing are mounted as the application,the functions or pieces of processing may be mounted using a residentapplication or an application such as HTML5. The API may be mounted asdata delivery and receipt between applications or a state notification.

Example of the functions of the API function relevant to the informationindicating whether the reference clocks are synchronized with each otherinclude the following items 1) to 9).

-   1) Information indicating whether the reference clock information on    the broadcasting content is identical to the reference clock    information on the communication content is acquired.-   2) Information indicating whether the reference clock    synchronization is required is acquired.-   3) The kind or synchronization method of each piece of reference    clock information is acquired.-   4) Information (such as timeline information) necessary for the    clock synchronization is acquired.-   5) The acquisition destination of the information necessary for the    clock synchronization is acquired.-   6) The clock information on a reference source is set to an    argument, and the clock information on a reference destination in    which the broadcasting content and the communication content are    synchronized with each other is returned. For example, in the case    that the broadcasting content and the communication content are not    synchronized with each other, a value indicating that the    broadcasting content and the communication content are not    synchronized with each other is returned.-   7) Each instruction to start the reference clock synchronization is    issued.-   8) A state indicating whether the reference clocks are synchronized    with each other is acquired.-   9) A notification that the reference clocks are synchronized with    each other is made.

[Reception Method]

An operation example in which the reception device determines whetherthe broadcasting content and the communication content are to besynchronously played back and plays back the broadcasting content andthe communication content in the case that the attribute information orthe location information is stored in the program information on thebroadcasting will be described below as a reception method of theseventh modification with reference to FIG. 16.

FIG. 16 is a flowchart illustrating an operation example on thereception side in the broadcasting and communication cooperation serviceof the seventh modification of the first exemplary embodiment. Theoperation of the flowchart in FIG. 16 can be applied to the broadcastingand communication cooperation service in which any combination ofmultiplexing systems such as the MMT, the DASH, and the RTP is used. Theoperation can also be applied to the hybridcast.

In FIG. 16, the determination whether the broadcasting content and thecommunication content are to be synchronized with each other iseliminated on the assumption that the broadcasting content and thecommunication content are to be synchronized with each other.

Because Steps S1101 and S1102 are similar to Steps S401 and S402 in FIG.9, the description is omitted.

In Step S1103, the reception device decides whether the communicationcontent is to be acquired. When the communication content is to beacquired (YES in S1103), the flow goes to Step S1104, and the data isreceived through both the transmission channels of the broadcasting andcommunication. Whether the reference clocks of the broadcasting contentand communication content are identical to or different from each otheris determined in Step S1105.

When the reference clocks of the broadcasting content and communicationcontent are different from each other (YES in S1105), the flow goes toStep S1106, and the reference clocks are synchronized with each other.The broadcasting content and the communication content are synchronouslyplayed back in Step S1107.

On the other hand, when the reference clocks of the broadcasting contentand communication content are identical to each other (NO in S1105), thereference clocks are not synchronized, but the synchronization playbackis performed using the common clock.

Whether the reference clocks need to be synchronized with each other maybe determined after the processing in Step S1105. For example, whether acapability of the reception device meets the clock synchronization,whether the receiver has the specification of the clock synchronization,or whether the user performs the clock synchronization is determinedaccording to the kind or method of the clock synchronization. Whetherthe broadcasting and communication reference clocks are to besynchronized with each other is comprehensively determined through theprocessing in Step S1105 and the above determination result, and theflow may go to Step S1106 or S1107.

The reference clock synchronization in S1106 may be performed in advanceof the reception in S1104. In the case that the playback of thereception data of the content is started after pre-buffering, sometimesthe reception data is decoded and played back after the confirmation ofthe reception of the data in which the PTS is T1 in the broadcastingcontent and the data in which the PTS is T1 in the communication content(at this point, it is assumed that the PTSs of the broadcasting contentand communication content are already synchronized with each other). Indetermining whether the synchronously played back pieces of data areprepared, it is necessary that the reference clocks of the broadcastingcontent and communication content are already synchronized with eachother.

In the case that the clock synchronization information cannot beacquired in Step S1106, or in the case that the clock synchronizationcannot be performed due to the specification of the receiver, sometimesthe broadcasting and communication cooperation service cannot beprovided to the user. In such cases, whether the data transmittedthrough the communication is to be received may be determined in StepS1103 based on whether it is necessary to perform the synchronization orwhether playback can be performed without performing thesynchronization.

In Step S1103, whether the data transmitted through the communication isactually to be received may be determined in consideration of all thepieces of information such as the user selection or user setting, thecontent provider or service provider, the intention of the broadcastingstation, the specifications of the reception device, and the intentionof the manufacturer in addition to the information that can beidentified by the transmission channel identification descriptor.

[Reception Device]

A configuration example of the reception device performing the operationin FIG. 16 will be described below. FIG. 17 is a block diagramillustrating the configuration example of the reception device of theseventh modification of the first exemplary embodiment.

Reception device 1100 in FIG. 17 includes identification informationacquisition part 1101, decision part 1102, communication combination-usedetermination part 1103, Loc information acquisition part 1104,broadcasting receiver 1105, communication receiver 1106, reference clockdetermination part 1107, and player 1108.

Because identification information acquisition part 1101 tocommunication reception part 1106 are similar to identificationinformation acquisition part 301 to communication reception part 306 inFIG. 8, the description is omitted.

Reference clock determination part 1107 has a function of performing theprocessing in Step S1105 of FIG. 16. Reference clock determination part1107 may determine whether the reference clock synchronization isrequired after determining whether the reference clocks are differentfrom each other.

When the reference clocks are different from each other, player 1108synchronizes the reference clocks with each other based on thedetermination result of reference clock determination part 1107, anddecodes and plays back the broadcasting content or the communicationcontent.

The function, the configuration of the reception device, and thereception method of the seventh modification are described above by wayof example. The function, the configuration of the reception device, andthe reception method of the seventh modification are not limited to theabove description, but any function, configuration of the receptiondevice, and reception method may be used as long as the similar functionand effect can be implemented.

[Effect of First Exemplary Embodiment and the Like]

As described above, the first exemplary embodiment can provide thetransmission method, reception method, transmission device, andreception device in which the reception side can play back the contentby the combination of the broadcasting and the communication even if thetiming of starting the reception of the content through thecommunication is delayed.

Specifically, the transmission method according to one aspect of thepresent disclosure for enabling transmission of content using thebroadcast wave and the communication channel, the transmission methodincludes the information transmission step of transmitting the auxiliaryinformation using at least the broadcast wave, the auxiliary informationfor synchronizing the content transmitted using the broadcast wave andthe content transmitted using the communication channel when the contentis transmitted using the broadcast wave and the communication channel,the auxiliary information causing the reception side to synchronize thecontent transmitted using the broadcast wave and the content transmittedusing the communication channel when the reception side receives theauxiliary information.

Thus, when the content is transmitted using the broadcast wave and thecommunication channel, the auxiliary information is transmitted in orderto synchronize the content transmitted using the broadcast wave and thecontent transmitted using the communication channel, so that thereception side can synchronize the content transmitted using thebroadcast wave and the content transmitted using the communicationchannel when receiving the auxiliary information.

In the information transmission step, the auxiliary information may betransmitted in advance of the transmission of the content, and theauxiliary information further may include location informationindicating an acquisition destination of the content or informationindicating an acquisition destination of the location information.

In the auxiliary information transmission step, the auxiliaryinformation may be transmitted while difference information between areference clock of the content transmitted using the broadcast wave anda reference clock of the content transmitted using the communicationchannel is included in the auxiliary information.

In the auxiliary information transmission step, when the referenceclocks of the pieces of content differ, the auxiliary informationtransmission may cause the reception side to achieve the synchronizationthrough synchronization of the reference clock of the contenttransmitted using the communication channel with the reference clock ofthe content transmitted using the broadcast wave based on the differenceinformation.

The transmission method may further include the generation step ofgenerating the content in a format compatible with MMT (MPEG MediaTransport), and the content transmission step of transmitting thecontent in the format generated in the generation step.

In the generation step, the content may be generated while the auxiliaryinformation is included in the message information being the informationon the acquisition of the content.

The reception method according to another aspect of the presentdisclosure includes: the reception step of receiving the contenttransmitted using the broadcast wave and the content transmitted usingthe communication channel; and the playback step of playing back thecontent transmitted using the broadcast wave and the content transmittedusing the communication channel while synchronizing the pieces ofcontent, when the auxiliary information for synchronizing the contenttransmitted using the broadcast wave and the content transmitted usingthe communication channel is received.

Thus, the service information transmitted through the transmissionchannel, such as the broadcast wave, which constitutes the entry point,is acquired, and the synchronization processing can be performed whenthe auxiliary information is included in the service information.

In the reception step, the content may be received by acquiring thecontent based on location information indicating an acquisitiondestination of the content when the auxiliary information is received inadvance of the reception of the content and the auxiliary informationincludes the location information.

In the reception step, the content may be received by acquiring locationinformation indicating an acquisition destination of the content basedon information indicating an acquisition destination of the locationinformation, and acquiring the content based on the acquired locationinformation when the auxiliary information is received in advance of thereception of the content and the auxiliary information includes theinformation indicating the acquisition destination of the locationinformation.

In the playback step, the content may be played back while thesynchronization is achieved through synchronization of the referenceclock of the content transmitted using the communication channel withthe reference clock of the content transmitted using the broadcast wavebased on the difference information when the auxiliary informationincluding difference information between a reference clock of thecontent transmitted using the broadcast wave and a reference clock ofthe content transmitted using the communication channel is received inthe reception step and the reference clock of the content transmittedusing the broadcast wave differs from the reference clock of the contenttransmitted using the communication channel.

The transmission device according to still another aspect of the presentdisclosure that can transmit the content using the broadcast wave andthe communication channel, the transmission device includes theinformation transmitter that transmits auxiliary information using atleast the broadcast wave, the auxiliary information for synchronizingthe content transmitted using the broadcast wave and the contenttransmitted using the communication channel when the content istransmitted using the broadcast wave and the communication channel, theauxiliary information causing the reception side to synchronize thecontent transmitted using the broadcast wave and the content transmittedusing the communication channel when the reception side receives theauxiliary information.

The reception device according to yet another aspect of the presentdisclosure includes: the reception part that receives the contenttransmitted using the broadcast wave and the content transmitted usingthe communication channel; and the playback part that plays back thecontent transmitted using the broadcast wave and the content transmittedusing the communication channel while synchronizing the pieces ofcontent, when the auxiliary information for synchronizing the contenttransmitted using the broadcast wave and the content transmitted usingthe communication channel is received.

As described above, in the first exemplary embodiment, theidentification information indicating whether the content including theaudio and the video is to be transmitted by the combination of thebroadcasting and the communication and, when the broadcasting andcommunication are used in combination, the information indicating thedependence relationship between the pieces of data transmitted throughthe transmission channels of the broadcasting and communication may begenerated and transmitted as the content management information. Forexample, the information indicating the dependence relationship betweenthe pieces of data may include whether the pieces of data transmittedthrough both the transmission channels are to be synchronously playedback. The information indicating the dependence relationship between thepieces of data may include whether the pieces of clock information onthe pieces of data transmitted through both the transmission channelsare identical to each other.

Thus, the transmission channel through which the content including theaudio and the video and the dependence relationship between the piecesof data transmitted through the different transmission channels areacquired in starting the reception of the content, so that the delaytime relevant to the decision of the asset to be received or theacquisition start of the communication content can be reduced.

In the first exemplary embodiment, the location information on the datatransmitted through the communication may be included in the contentmanagement information. For example, the location information on thetransmitted data may be the MPD in the MPEG-DASH. Not the data entity ofthe location information on the MPD but the information indicating theacquisition destination of the location information may be stored in thecontent management information.

Thus, the transmission channel through which the content including theaudio and the video and the dependence relationship between the piecesof data transmitted through the different transmission channels areacquired in starting the reception of the content, so that the delaytime relevant to the decision of the asset to be received or theacquisition start of the communication content can be reduced.

In the first exemplary embodiment, the reception device may analyze thecontent management information, and decide the transmission channelthrough which the content is received and the data received through eachtransmission channel. For example, in the case that the pieces of clockinformation on the pieces of data transmitted through the transmissionchannels are different from each other, auxiliary information necessaryfor the clock synchronization between the pieces of data is acquired,and the DTSs or PTSs of the pieces of data may be decoded and playedback while synchronized with each other. In the case that the pieces ofdata transmitted through the transmission channels are to besynchronously played back, the auxiliary information necessary for theclock synchronization between the pieces of data is acquired, and theDTSs or PTSs of the pieces of data may be decoded and played back whilesynchronized with each other.

Thus, the reception device that receives only the broadcasting data canmeet the playback of the communication data while being able to playback the broadcasting data by the operation similar to that of thereception of the conventional broadcasting.

A mechanism that synchronously plays back the broadcasting data and thecommunication data can be provided to the reception device.

Even if the clocks of the pieces of data transmitted through theplurality of transmission channels are not synchronized with each other,the clocks can be synchronized with each other by acquiring theauxiliary information necessary for the clock synchronization, and thepieces of data can synchronously be played back.

Second Exemplary Embodiment

In transmitting the information whether the stream transmitted throughthe broadcasting and the stream transmitted through the communicationare the synchronization playback target or the information indicatingthe dependence relationship between the streams transmitted through thetransmission channels, the transmission method and the reception methodfor receiving the pieces of information are described in the firstexemplary embodiment.

Desirably playback control is performed in the application in the casethat the reception device flexibly plays back the content while useroperation is involved as in the case that the user selects the playbacktarget from the selectable audio and video or a single-view full screendisplay is switched to multiview display in a video screen.

Mainstream applications are based on a widely-spread HTML (Hyper TextMarkup Language) browser. In the case that the application is the HTML,the playback control can be performed by interpreting the HTML. HTML hasan advantage of selecting or switching the content and of flexiblydescribing a layout change.

For example, in the hybridcast defined by the IPTV forum, theidentification information, such as ait_identifier_info( ), whichindicates the existence of the application, is transmitted in the datathat is always referred to in starting the reception of the broadcastingprogram such as the descriptor of the PMT in the TS and the descriptorof the MPT in the MMT. In the reception device compatible with thehybridcast, in the case that the identification information exists,application control information such as the AIT is acquired from thesection or data carousel in the TS or the information corresponding tothe MMT message or data carousel or by the download through thecommunication network. Then, the application such as the HTML file isacquired based on the application control information.

Hereinafter, application control information or the data of theapplication is referred to as application-related data. The applicationmay be described using description languages such as an XML other thanthe HTML.

[Method for Transmitting Default Service Information]

In the case that the receiver that is not compatible with theapplication exists, or even if the receiver is compatible with theapplication, a time lag from the tuning start in the broadcasting orcommunication is generated until the application is started since theapplication is acquired.

Accordingly, default setting information on the stream to be played backor the display layout may be transmitted in not the application-relateddata but the data, such as the PMT and the MPT, which is always acquiredduring the tuning, or the data, such as another TS section and the MMTmessage, which can be acquired with a delay shorter than a timenecessary for the start of the application. The information used forperforming the advanced playback control may be transmitted as theapplication data of the HTML.

Examples of the information relevant to the playback control of thestream transmitted through the broadcasting or communication include (a)information on the scalability between the streams, (b) information onswitching of streams such as multilingual voices or videos havingdifferent bit rates, (c) simultaneous display information such asinformation indicating the plurality of video streams that cansimultaneously be displayed, and information on the layout during thesimultaneous display. Default values of these pieces of information arereferred to as default playback control information.

In the reception device that is not compatible with the application, theplayback is performed based on the default value. On the other hand, thereception device compatible with the application starts the playbackbased on the default value, and switches the playback operation afterthe start of the application based on the user operation or a controlcommand of the application.

The playback operation may be switched by the application only for theinformation that can be switched by the user operation. For example, thesimultaneous display can basically be switched by the user. For the timescalability, the receiver may automatically decide the playbackoperation such that the extension layer is always used when the streamof the extension layer can be acquired. In this case, the information onthe time scalability is transmitted only in the default playback controlinformation.

In the TS, the information on the playback control is basicallyperformed by the application, and the information on the scalability maybe transmitted in the default playback control information. At thispoint, only the information correlating the stream of the basic layerand the stream of the extension layer may be transmitted by the defaultplayback control information or the descriptor defined by the MPEG-2 TS,and the application side may decide whether the extension layer is to bedecoded based on the control command of the application or the useroperation.

The playback operation may be switched by the application only for theinformation relevant to the layout. For example, the time scalability orthe stream switching does not involve the layout change. Accordingly,these pieces of information are transmitted only in the default playbackcontrol information. On the other hand, in the information on thesimultaneous display, the playback operation can be performed by theapplication because the switching is possibly performed by the useroperation.

(Description Example of Default Playback Control Information)

A description example of the playback control information in switchingthe playback operation of the default playback control information usingthe application will be described below. It is assumed that the defaultplayback control information is stored in the descriptor, and that theapplication control information is described in the HTML.

FIG. 18A is a view illustrating a description example of the defaultplayback control information of the second exemplary embodiment, andFIG. 18B is a view illustrating a video display example according to thelayout information of the default playback control information in FIG.18A. In the default playback control information of FIG. 18A, the fullscreen display of the video of PID=100 is indicated by the layoutinformation as illustrated in FIG. 18B.

In the layout information, only the full screen display may be indicatedwithout indication of information specifying the stream. At this point,in the case that at least two video streams exist, the full screendisplay of the video played back in default can be performed wheninformation (application control information) specifying the video to beplayed back in default is separately indicated.

FIG. 19A is a view illustrating an example of the application controlinformation of the second exemplary embodiment, and FIG. 19B is a viewillustrating a video display example according to the layout informationof the application control information in FIG. 19A.

In the application control information of FIG. 19A, two display areas ofarea 1 and area 2 are set by a Layout tag. As illustrated in FIG. 19B,the video of PID=100 is displayed in area 1, and the video of PID=200 isdisplayed in area 2.

Accordingly, the reception device that receives the HTML applicationcontrol information in FIG. 19A displays the video of PID=100 and thevideo of PID=200 in area 1 and area 2, respectively. The informationspecifying the video may be the URL or the packet ID of the MMT packetin addition to the PID.

Thus, in the example of FIGS. 19A and 19B, the default playback controlinformation indicates the two kinds of information, namely, thescalability and the layout. The scalability indicates that the kind ofthe scalability is the time scalability, the video of PID=100 is thebasic layer, and the video of ID=200 is the extension layer. The layoutinformation indicates the full screen display of the video of PID=100.

Assuming that the frame rate of 60 fps only in the basic layer increasesto 120 fps using the extension layer, only the video of PID=100 isdecoded and the video image corresponding to 60 fps is played back bythe full screen display in the default state. In the case that streamattribute information such as the stream type of the MPEG-2 systemseparately indicates the transmitted stream corresponds to the basiclayer or extension layer of the scalability, these pieces of informationdoes not need to be described in the default playback controlinformation. When only the basic layer is to be decoded and played backin the default state is separately defined, the layout information mayonly indicate the full screen display.

FIG. 20A is a view illustrating another description example of thedefault playback control information of the second exemplary embodiment,and FIG. 20B is a view illustrating a video display example according tothe layout information of the default playback control information inFIG. 20A. FIG. 21A is a view illustrating an example of the applicationcontrol information of the second exemplary embodiment, and FIG. 21B isa view illustrating a video display example according to the layoutinformation of the application control information in FIG. 21A.

In FIG. 21A, function A is defined by a Script tag. Function A is afunction of issuing an instruction to decode and play back the extensionlayer of the time scalability when a button on the screen is pressed,and the index number specifying the basic layer and the extension layeris indicated as an argument. A Body tag describes that function A iscalled in the case that a specific button of a remote controller ispressed.

When the button is pressed, the reception device that receives the HTMLapplication in FIG. 21A decodes the stream of the extension layer ofPID=200, and plays back the video image corresponding to 120 fps by thefull screen display.

The audio or video stream played back in default may separately beindicated using the MPEG-2 system or the MMT descriptor. For example,the streams played back in default can be grouped, and a group ID andthe stream can be correlated with each other. Alternatively, thedescriptor indicating the stream played back in default may be defined,and a list of PIDs of the streams played back in default can be includedin the descriptor.

A default value may be previously defined in the default playbackcontrol information to eliminate the need of transmission of the defaultplayback control information in the case that a parameter value is equalto the default value. For example, when the full screen display is setto the default value as the layout, the layout information does not needto be included for the full screen display. At this point, in the casethat the full screen display is not compatible with the stream switchwhile the scalability is not used, the default playback controlinformation does not need to be transmitted.

[Reception Method]

In the second exemplary embodiment, the reception side acquires theservice information, and subsequently analyzes the default playbackcontrol information and the playback control information provided by theapplication, and is operated. A reception method of the second exemplaryembodiment will be described below with reference to the drawings.

FIG. 22 is a flowchart illustrating an operation example on thereception side of the second exemplary embodiment. FIG. 22 illustratesan example of the operation to decide the layout in the case that thedefault playback control information and the playback controlinformation provided by the application are analyzed to present thescalability, the stream switching function, and the content.

In Step S701, the reception side selects content to be viewed.

In Step S702, the reception side analyzes the default playback controlinformation, decides the stream to be decoded and played back, anddecides the layout presentation method.

The default playback control information may be transmitted whileincluded in the PMT or MPT data that is always acquired during thetuning, or the default playback control information may be transmittedby the MPEG-2 TS section or MMT message that is transmitted separatelyfrom the application-related data.

In the case that the default playback control information is to betransmitted by the section or message, the default value of the defaultplayback control information is set, and the operation may be performedbased on the default value of the default playback control informationuntil the section or the message is received. The stream to be decodedand played back may be decided by referring to the descriptor indicatingthe audio or video stream played back in default.

In Step S703, the playback is started according to the decided playbackcontrol parameter.

In Step S704, whether the application is to be received is determined.The processing is ended when the application is not to be received (NOin S704). On the other hand, when the application is to be received (YESin S704), the flow goes to Step S705, and whether the playback controlfunction is indicated in the application is determined.

When the playback control function is not indicated (NO in S705), theprocessing is ended. When the playback control function is indicated(YES in S705), the flow goes to Step S706, and the playback controlinformation is updated in response to the control command or the useroperation based on the playback control function indicated by theapplication.

In Step S707, the playback is performed according to the updatedplayback control parameter, and the processing is ended.

[Reception Device]

FIG. 23 is a block diagram illustrating a configuration example of areception device of the second exemplary embodiment. FIG. 23 illustratesthe configuration example of the reception device that performs theoperation in each step of FIG. 22.

Reception device 700 in FIG. 23 includes receiver 701, defaultinformation analyzer 702, application information reception part 703,application playback control information analyzer 704, and playbackcontrol performing part 705. Because the operations of these parts aresimilar to those in the steps of FIG. 22, the description is omitted.

(First Modification)

The mechanism that updates the default playback control informationusing the application can be applied to the single broadcasting, thesingle communication, the transmission of the content by the combinationof the broadcasting and the communication.

The technical thought of the second exemplary embodiment can also beapplied to the MPEG-2 TS timeline extension (13818-3: 2013/AMD6) that iscurrently standardized in the MPEG. In the TS timeline extension, intransmitting the content using the plurality of multiplexing streamsincluding at least one TS (referred to as a basic TS), informationsynchronizing the basic TS with the reference clock used in the decodingor display of the content in other multiplexing streams is provided.

Specifically, a timeline extending access unit including informationcorrelating the reference clock of the multiplexing stream differentfrom the basic TS with the PCR of the basic TS is defined, and thetimeline extending access unit is stored in a PES packet, andtransmitted in the form of TS packet. In the timeline extending accessunit, the timeline extending information is expressed in the format ofthe descriptor of the MPEG-2 system. The timeline extending informationis transmitted in a PES packet unit. Therefore, the reference clocksynchronization with the updated PCR can rapidly be performed even ifthe PCR is discontinuously generated.

However, because generally the discontinuous PCR is not generated in thebroadcasting program, the timeline extending information is received instarting the reception of the broadcasting program, and the referenceclocks are synchronized with each other. Therefore, the necessity ofre-synchronization is frequently eliminated in the broadcasting program.

Accordingly, in the case that it is guaranteed that the discontinuousPCR is not generated in the broadcasting program, the default value ofthe timeline extending information is stored in the PMT, but thetimeline extending access unit does not need to be transmitted. Forexample, in the timeline extending access unit, the descriptor similarto the descriptor in which the timeline extending information is storedcan be stored in the PMT section, and used as the default value of thetimeline extending information. Both the timeline extending access unitand the default information stored in the PMT may be used.

In the case that it is guaranteed that the discontinuous PCR is notgenerated in the broadcasting program or until a specific clock timewhile the timeline extending access unit is transmitted, after the clocksynchronization is performed based on the information on the timelineextending access unit received immediately after the tuning, there-synchronization does not need to be performed in the broadcastingprogram or until the specific clock time.

In the case that the timeline extending information is transmitted bythe section, the timeline extending information corresponding to theupdated PCR may be transmitted for a given period since the generationof the discontinuous PCR. In the reception device, when the versionnumber of the section is updated, the re-synchronization is performedbased on the timeline extending information included in the section. Theclock synchronization between the streams cannot be guaranteed at theclock time after the generation of the discontinuous PCR and before there-synchronization. At this point, the discontinuity of the PCR isseparately detected based on information, such as a TS discontinuityindicator, which indicates the discontinuity of the PCR. When thediscontinuity of the PCR is detected, the decoding and display areperformed until the re-synchronization on the assumption that the basicTS and the access unit of the media being the synchronization target areset to a fixed frame rate.

[Effect of Second Exemplary Embodiment and the Like]

As described above, in the second exemplary embodiment, when the layoutinformation on the video display or the playback control informationincluding the information indicating the stream that is switchableduring the playback is transmitted in the content including the audio orvideo, the default value of the playback control information is storedin the data that is always received during the tuning, and theinformation used for updating the default playback control operation istransmitted while stored in the information relevant to the applicationsuch as the hybridcast.

In the case that the playback is started according to the default valueof the playback control while the reception device is compatible withthe application, the default playback control information is updated inresponse to the user operation based on the playback control functiontransmitted as the application data.

Thus, the delay time necessary for the decision of the parameterrelevant to the playback control of the content layout content can bereduced.

Third Exemplary Embodiment

As described above, in the MMT system, the video and audio aremultiplexed and packetized, and transmitted through at least onetransmission channel such as the broadcasting and the communication. Thereception device can receive the packet transmitted through at least onetransmission channel, extract the desired packet from the packets thatare received based on the program information, and perform the decodingand the presentation.

That is, in the MMT system, the media (such as the video image, voice,and the subtitle) transmitted through the plurality of transmissionchannels can be received to configure the program. However, the programcannot be configured using both the data accumulated by the downloadthrough the broadcasting or communication and the data streamed throughthe broadcasting or communication.

Therefore, a transmission method and a reception method in the case thatthe program is configured using both the data accumulated by thedownload through the broadcasting or communication and the data streamedthrough the broadcasting or communication will be described in a thirdexemplary embodiment.

The MMT (MPEG Media Transport) standardized by MPEG will be describedbelow as an example of the broadcasting-side multiplexing format in thebroadcasting and communication cooperation service.

In the MMT, the program information is transmitted by the table such asthe MPT (MMT Package Table) or message information such as the PA(Package Access) message. The asset (the single medium such as the audioand the video) constituting the program or the location informationtransmitting the asset are described in the MPT. One asset can also betransmitted through the plurality of transmission channels.

In the third exemplary embodiment, the transmission side also transmitsthe content (data or asset) using the broadcast wave and thecommunication channel, and transmits the service information in advanceof the content transmission.

[Service Information]

FIG. 24 is a view illustrating an example of the data structure of theservice information in the broadcasting and communication cooperationservice of the third exemplary embodiment. FIG. 25 is a viewillustrating an example of information included in a programconfiguration information descriptor of the third exemplary embodiment.

As illustrated in FIG. 24, the program configuration informationdescriptor is included in the MPT, and the program configurationinformation descriptor indicates the information on the assetconstituting the package. The information on the asset constituting thepackage can includes the following items.

(Information on Asset)

1) Information indicating whether the asset constituting the programincludes an accumulated asset (hereinafter, referred to as anaccumulative asset) may be included in the program configurationinformation descriptor as the information on the asset. As used herein,the accumulated asset means the asset that is accumulated in, forexample, a memory such as an HDD or an internal memory, an SSD, and anSD card or a Blu-ray disc.

2) In the case that the asset constituting the program includes theaccumulative asset, information indicating the program configuration maybe included in the program configuration information descriptor as theinformation on the asset.

For example, information indicating the program configuration may beincluded. Examples of such information is information indicating thatthe program is constructed only with the accumulative asset, informationindicating that the program is constructed with the accumulative assetand the transmitted asset (hereinafter, referred to as a transmissionasset), or information indicating that the program is constructed withthe asset including the accumulative packet and the transmission asset.For example, in the case that the program is constructed with thescalably-coded video image, information indicating that the transmissionasset includes the basic layer while the accumulative asset includes theextension layer may be included. Information indicating whether thedecoding or the playback of the accumulative asset is required for theplayback of the program may be included. For example, in the case thatthe content of the accumulative asset is additional information, theplayback can be deemed to be not necessary, and information indicatingthat the playback of the accumulative asset is not necessary may beincluded.

For example, in the case that the reception device is not compatiblewith the accumulation, or in the case that the accumulative asset is notaccumulated, the program can be played back using the asset acquiredthrough the broadcasting or communication with no use of theaccumulative asset based on the information indicating that the decodingor the playback of the accumulative asset is not necessary for theplayback of the program.

3) The information on the accumulative asset may be included in theprogram configuration information descriptor as the information on theasset.

For example, a) the attribute information such as accumulation format ofthe accumulative asset, the video or voice coding system, thetransmission system in which the accumulative asset is transmitted, andthe multiplexing system may be included. In this case, the attributeinformation is previously provided to the accumulative asset, and theattribute information may be included in the header of the accumulativeasset or the program information indicating the configuration of theaccumulative asset. The reception device can perform the playback whenthe attribute information stored in the program information is matchedwith the attribute information on accumulative asset. For example, b)information on capability and function of the receiver which arenecessary for the playback of the program including the accumulativeasset may be included. For example, c) information (scramble system,viewing limit, conditional access, and copyright information)restricting the playback or viewing of the program or a key may beincluded. In this case, the reception device may check the viewingrestriction information stored in the program information against theaccumulative asset to determine whether the accumulative asset can beplayed back or viewed. The reception device may accumulate thepreviously-encrypted asset, and decode the encryption of theaccumulative asset based on the transmitted key.

4) In the case that the asset constituting the program is constructedwith the transmission asset and the accumulative asset, the clock timeinformation used for synchronizing and playing back the transmissionasset and the accumulative asset may be included in the programconfiguration information descriptor as the information on the asset.

For example, the clock time information may indicate an offset amount ofthe reference clock time information on the transmission asset to thereference clock time serving as the reference of the time stamp providedto the accumulative asset. In the case that the time stamp is providedto the accumulative asset based on the PCR (Program Clock Reference) orthe NTP (Network Time Protocol), the relative clock time relative to thetransmitted reference clock time (PCR or NTP) may be indicated. In thecase that the accumulative asset is accumulated in a format having arandom access table, the clock time information may be a clock timeinformation table of the transmission asset relative to a random accesspoint of the accumulative asset.

(Location Information)

In the MPT, the location information on the asset is described in eachasset. For example, in the case that one asset exists in the pluralityof locations, the plurality of pieces of location information aredescribed in the MPT.

FIG. 26 is a view illustrating an example of information included in thelocation information descriptor of the third exemplary embodiment. FIG.27 is a view illustrating an example of a location type included in thelocation information descriptor of the third exemplary embodiment.

As illustrated in FIG. 26, in the location information descriptor, alocation type and an identifier specifying the asset corresponding tothe location type are described as the location information.

The location type expresses location information. In an example of FIG.26, because the location type has a value Value of 0xA0 (Value=0xA0),the data is accumulated in Local as illustrated in FIG. 27. In the casethat the location type indicates that the data is accumulated in Local,a local ID uniquely indicating the accumulated data is described in thelocation information.

For example, the local ID may be the asset ID of the accumulated assetor the packet ID. The local ID may be a 32-bit transport file identifierdefined in ARIB STD-B45, or newly defined. Various IDs such as a networkID and a stream ID may be combined to generate the local ID according toa predetermined naming rule. A broadcasting station, a transmissionstation, a content provider, and the like may previously provide thelocal ID, or the receiver side may add corrected or additionalinformation to the ID. The reception side may provide the original ID sothat the data can be specified by preparing a table indicating acorrelation with the ID provided on the transmission side.

The above example indicates that the asset is accumulated in Local usingthe location type, and the local ID is separately provided.Alternatively, the following method may be adopted. For example, datamay be specified by selecting IPv4 as the location type, and using an IPaddress unique to Local. For example, in the case that the IP address is192.168.xxx.xxx, the asset may be deemed to be accumulated in Local, andthe asset accumulated in the portion of xxx.xxx may be specified.

The local ID is provided to the data (file) of the accumulative asset.For example, the local ID is stored in the file header of the file. Thelocal ID may previously be stored in the broadcasting station,transmission station, or the content provider, or stored on thereception side.

The above descriptor is described by way of example. Alternatively, thedescriptor may be constructed with the data structure having the similarfunction. The descriptor and identifier of the third exemplaryembodiment may be stored in the table or message indicating informationin the package unit different from the MPT. The transmission may beperformed using another piece of signaling information.

Although the MMT is described by way of example, the format is notlimited to the MMT. Alternatively, other format such as the TS and theMPEG-DASH may be used. For example, in the case that the MPEG2-TS isused as the multiplexing system, the descriptor may be stored in the PMT(Program Map Table). In the case that the data is transmitted by thecombination of the MPEG2-TS system and another system, the descriptormay be stored in the TEMI (Timeline and External Media Information)access unit. In the case that the MPEG-DASH is used, the description maybe made in MPD (Media Presentation Description).

(Asset Configuration Information Descriptor)

In the MMT system, one asset can be transmitted through the plurality oftransmission channels. At this point, an asset configuration informationdescriptor indicating an asset configuration may be stored.

FIG. 28 is a view illustrating an example of information included in theasset configuration information descriptor of the third exemplaryembodiment. The information indicating the asset configuration caninclude the following items.

1) Information indicating that the asset is the accumulative asset orinformation indicating that the asset includes the accumulative packetmay be included in the information indicating the asset configuration.As used herein, the case that the asset includes the accumulative packetmeans the case that one asset is constructed with the packet transmittedthrough the broadcasting or communication and the accumulated packet.

2) In the case that the asset is the accumulative asset, for example, a)the information indicating that the asset is constructed only with theaccumulative asset and the information indicating that the asset isconstructed with the accumulative packet and the transmission packet maybe included as the information indicating the asset configuration. b) Inthe case that the asset is constructed with the scalably-coded videoimage, for example, information indicating that the transmission packetincludes the basic layer while the accumulative packet includes theextension layer may be included as the information indicating the assetconfiguration. c) Information indicating whether the decoding andplayback of the accumulative packet are required for the assetconfiguration may be included as the information indicating the assetconfiguration. For example, in the case that the content of theaccumulative packet is additional information, the playback can bedeemed to be not necessary, and information indicating that the playbackof the accumulative packet is not necessary can be indicated.

Thus, in the case that the reception device is not compatible with theaccumulation, or in the case that there is no accumulative packet, theprogram can be played back using the packet acquired through thebroadcasting or communication with no use of the accumulative packetbased on the information indicating that the decoding or the playback ofthe accumulative packet is not necessary for the playback of the asset.

The asset configuration information descriptor is described by way ofexample. Alternatively, the asset configuration information descriptormay be configured by the data structure having the similar function.

The asset configuration information descriptor and the identifier may bestored in the table or message indicating information in the packageunit different from the MPT. The transmission may be performed usinganother piece of signaling information.

Although the MMT is described by way of example, the format is notlimited to the MMT. Alternatively, other format such as the TS and theMPEG-DASH may be used. For example, in the case that the MPEG2-TS isused as the multiplexing system, the descriptor may be stored in the PMT(Program Map Table). In the case that the data is transmitted by thecombination of the MPEG2-TS system and another system, the descriptormay be stored in the TEMI (Timeline and External Media Information)access unit. In the case that the MPEG-DASH is used, the description maybe made in MPD (Media Presentation Description).

[Reception Method and Reception Device]

An example of the operation in which the reception device of the thirdexemplary embodiment synchronously plays back the accumulative assetwill be described below with reference to the drawings.

FIG. 29 is a flowchart illustrating a reception method in thebroadcasting and communication cooperation service of the thirdexemplary embodiment. FIG. 30 is a block diagram illustrating aconfiguration example of a reception device of the third exemplaryembodiment.

Reception device 30 in FIG. 30 includes program information analyzer 31,accumulative asset specification part 32, accumulative asset informationanalyzer 33, determination part 34, asset acquisition part 35,synchronization and presentation part 36, and synchronization controller37.

In Step S11, program information analyzer 31 analyzes the programconfiguration information descriptor constituting the entry point, andanalyzes whether the accumulative asset is included in the programconfiguration.

In Step S12, program information analyzer 31 determines whether theaccumulative asset is included in the element constituting the program.When the accumulative asset is included in the element constituting theprogram (YES in S12), the flow goes to Step S13 to acquire theinformation indicating the program configuration, the information on theaccumulative asset, and the relative clock time information relative tothe accumulative asset. When the accumulative asset is not included (NOin S12), the flow goes to Step S17, the transmission asset transmittedthrough the broadcasting or communication is acquired, and synchronouslyplayed back.

In Step S14, reception device 30 acquires the location information onthe accumulative asset and the local ID. More specifically, in the casethat the asset is locally accumulated, accumulative asset specificationpart 32 searches and specifies the asset corresponding to the local IDfrom the assets accumulated in reception device 30. In the case that theplurality of accumulation devices exist, the asset may be searched fromthe plurality of accumulation devices, or searched only from a specificaccumulation device. Accumulative asset information analyzer 33 acquiresthe attribute information on the specified asset.

In Step S15, determination part 34 determines whether the programincluding the accumulative asset can be played back based on theaccumulative asset information acquired in Step S12 and the accumulativeasset attribute information acquired in Step S14.

When the program can be played back (YES in S15), the flow goes to StepS16, asset acquisition part 35 acquires the accumulative asset inaddition to the transmission asset transmitted through broadcasting orcommunication. Based on the acquired relative clock time information,synchronization controller 37 performs synchronization controlprocessing on the transmission asset and the accumulative asset, andsynchronization and presentation part 36 synchronizes and presents theprogram.

On the other hand, when the program cannot be played back (NO in S15),the flow goes to Step S17, the transmission asset transmitted throughthe broadcasting or communication is acquired, and synchronously playedback.

[Effect of Third Exemplary Embodiment and the Like]

As described above, the third exemplary embodiment can implement theprogram information generation method, the program playback method, andthe playback device in multiplexing the broadcasting and communicationcooperation service in the format such as the MMT (MPEG Media Transport)system currently standardized in the MPEG (Moving Picture Expert Group).

The MMT system multiplexes and packetizes the video and audio, andtransmits the multiplexed and packetized video and audio through atleast one transmission channel such as the broadcasting and thecommunication, and the reception device receives the packet transmittedthrough at least one transmission channel, extracts the desired packetfrom the packets that are received based on the program information, andperforms the decoding and the presentation.

In the MMT system, the media (such as the video image, voice, and thesubtitle) transmitted through the plurality of transmission channels canbe received to configure the program. However, the program cannot beconfigured using both the data accumulated by the download through thebroadcasting or communication and the data streamed through thebroadcasting or communication.

In third exemplary embodiment, the identifier indicating that one ofmedia constituting the program is the accumulated data and theidentifier that can specify the accumulated medium (file) are providedin the program information indicating the program configuration. Theplayback device analyzes the program information, specifies the mediumtransmitted through the broadcasting and communication and theaccumulated data, and synchronously plays back the media and theaccumulated data.

Thus, the program is constructed using both the data accumulated by thedownload through the broadcasting or communication and the data streamedthrough the broadcasting or communication, so that the servicecooperated with the accumulated file can be provided in addition to theconventional broadcasting and communication cooperation service.

In third exemplary embodiment, the combination of the transmission assetand the accumulative asset is described by way of example.Alternatively, the transmission asset may be the asset transmittedthrough the broadcasting or the asset transmitted through thecommunication. The transmission asset may be the asset transmittedthough both the broadcasting and the communication. The followingservice may be provided as the service in which the accumulative assetis used. An identifier indicating the service content may be stored inthe program information.

(Service in Which Accumulative Asset is Used)

1) The asset constituting the program may be previously downloaded, andonly the program information or clock time synchronizing information(such as the clock time reference information or the relative value ofthe time stamp) may be transmitted through the broadcasting, and theprogram may be played back using the accumulative asset. At this point,the broadcaster can provide the program in which the accumulated data isused to viewers in real time along a broadcasting program schedule. Theviewers can view the accumulated data as if the viewers view thebroadcasting program that is broadcasted in real time. Not only thereal-time broadcasting but also on-demand content can be provided.

2) The program information or the random access point may be previouslydownloaded and accumulated together with the asset constituting theprogram, and the program information or the random access point mayconstruct the program while being synchronized with the programinformation transmitted through the broadcasting or communication.

3) The normal broadcasting program can be transmitted only through thebroadcasting while the service cooperated with the accumulated data isprovided only during a commercial message. The commercial message datamay be previously downloaded through the broadcasting or communicationto provide the program including the accumulated data to the viewers ina commercial message time slot. The plurality of pieces of commercialdata may be previously downloaded to enable selection of the commercialmessage to be provided according to the attribute or preference of theviewer. The attribute or preference of the viewer may be acquired andanalyzed by the reception device, or acquired in cooperation withanother application or service.

4) The broadcaster may allocate an empty frequency resource to anotherservice by providing the service cooperated with the accumulated data.At this point, information indicating that a frequency resource used inthe service is being provided to another service may be stored in theprogram information.

5) A function in which the viewer switches the program to the programcooperated with the accumulative asset may be included. For example, theviewer who views only the transmission asset may switch to the programincluding the accumulative asset using an user interface such as aremote controller.

6) The reception device or the viewer may set whether to gain the accessto the accumulative asset to construct the program. The access to theaccumulative asset to construct the program may be enabled only in thecase that the program information is guaranteed to be reliable. A key orthe like may be stored in information indicating that the programinformation is reliable.

(EPG)

7) The information displayed as EPG (Electronic Program Guide) may beacquired from the program information or the signaling informationdedicated to the EPG.

8) Information indicating whether the program is to be provided throughthe broadcasting, through the communication, using the accumulation, bythe combination of the broadcasting and the communication, or as theextension service may be displayed on the EPG. Only the function thatcan be provided by the reception device may be displayed. For example,in the case that the reception device does not have the accumulationfunction or the communication reception function, information on theaccumulation or the communication does not need to be displayed.

9) In the case of the program including the accumulative asset,information indicating whether the accumulative asset of the program isaccumulated may be displayed on the EPG. Information indicating whetherthe accumulative asset of the program can be provided may be displayedon the EPG. The information may be indicated by a character or abackground color of the program of the EPG. The content including theaccumulative asset may present information on the viewing limit or thecopyright.

10) In the case that the program including the accumulative asset isreserved from the EPG, information indicating whether the accumulativeasset can be downloaded through the broadcasting, can be downloadedthrough the communication, or can be viewed by the communicationstreaming may be displayed on the EPG. In the case that the receptiondevice does not include the communication means, only the informationindicating whether the accumulative asset can be downloaded through thebroadcasting may be displayed. The viewer selects any method that canachieve the timer download and reserves the program.

The timer download may previously be set from the EPG by the viewer, orthe reception device may automatically perform the download. The viewermay select the download method, or the reception device mayautomatically select the download method.

The display of the EPG or the function of the reception device may bechanged according to time slot in which the download can be performedthrough the broadcasting, the time slot in which the download can beperformed through the communication, and the time slot in which thedownload can be performed by the communication streaming.

The presentation method is not limited to the EPG display mentionedabove, but may be another method other than the EPG.

Although the transmission method and reception method of the exemplaryembodiments of the present disclosure are described above, the presentdisclosure is not limited to the exemplary embodiments. Variousmodifications of the exemplary embodiments conceived by those skilled inthe art and the combinations of the components of the differentexemplary embodiments may also be included in the present disclosure aslong as the modifications and combinations do not depart from thepresent disclosure.

For example, in the exemplary embodiments, each component may beconstructed with dedicated hardware, or implemented by executing asoftware program suitable for the component. Each component may beimplemented such that a program execution part such as a CPU and aprocessor reads and executes the software program recorded in a harddisk or a recording medium such as a semiconductor memory.

The present disclosure is useful for the content transmission andreception methods for enabling transmission of content using thebroadcast wave and the communication channel.

What is claimed is:
 1. A transmission method for enabling transmissionof content using a broadcast wave and a communication channel, thetransmission method comprising: generating a first content data and asecond content data; transmitting auxiliary information using at leastthe broadcast wave or the communication channel, the auxiliaryinformation being information for synchronizing the first content dataand the second content data; hybrid-transmitting the first content dataand the second content data, the first content data being transmittedusing the broadcast wave and the second content data being transmittedusing the communication channel so that the first content data and thesecond content data constitute the content, and when the content ishybrid-transmitted using the broadcast wave and the communicationchannel, the auxiliary information causing a reception side to performthe synchronization when the reception side receives the auxiliaryinformation; wherein, in the transmitting of the auxiliary information,the auxiliary information includes attribute information indicating thatthe first content data and the second content data constitute thecontent and location information that indicates an acquisitiondestination of the content or information indicating an acquisitiondestination of the location information, the first content data and thesecond content data are (i) identical video and audio data eachindicating the content, or (ii) video data, audio data, or video andaudio data that constitute the content, and the auxiliary informationalso includes information indicating a format of meta-information onplayback control of the content transmitted using the communicationchannel, the meta-information on the playback control includinginformation on scalability between streams.
 2. The transmission methodaccording to claim 1, wherein the transmitting of the auxiliaryinformation includes transmitting the auxiliary information beforehybrid-transmitting the content.
 3. The transmission method according toclaim 1, wherein, in the generating of the first and second content dataconstituting the content, the content is generated while the auxiliaryinformation is included in message information that is informationrelating to the acquisition of the content.
 4. A reception methodcomprising: receiving content hybrid-transmitted as first content datatransmitted using a broadcast wave and a second content data transmittedusing a communication channel; and playing back the content transmittedusing the broadcast wave and the content transmitted using thecommunication channel by synchronizing the first content datatransmitted using the broadcast wave and the second content datatransmitted using the communication channel so that the first contentdata and the second content data constitute the content, when auxiliaryinformation for synchronizing the content transmitted using thebroadcast wave and the content transmitted using the communicationchannel is received, wherein, in the playback of the content, thecontent is played back while the synchronization is performed, when theauxiliary information including attribute information indicating thatthe first content data and the second content data constitute thecontent and location information that indicates an acquisitiondestination of the content or information indicating an acquisitiondestination of the location information is received in the receivingstep, the first content data and the second content data are (i)identical data each indicating the content, or (ii) video data, audiodata, or video and audio data that constitute the content, and theauxiliary information also includes information indicating a format ofmeta-information on playback control of the content transmitted usingthe communication channel, the meta-information on the playback controlincluding information on scalability between streams.
 5. The receptionmethod according to claim 4, wherein the receiving of the contentincludes receiving the auxiliary information before receiving thecontent, and the content is received by acquiring the content based onthe location information.
 6. The reception method according to claim 4,wherein the receiving of the content includes receiving the auxiliaryinformation before receiving the content, and the content is received byacquiring the location information based on information indicating theacquisition destination, and acquiring the content based on the acquiredlocation information when the auxiliary information includes theinformation indicating the acquisition destination of the locationinformation.
 7. A transmission device that can transmit content using abroadcast wave and a communication channel, the transmission devicecomprising: a transmitter that generates a first content data and asecond content data, transmits auxiliary information using at least thebroadcast wave or the communication channel, the auxiliary informationbeing information for synchronizing the first content data and thesecond content, and hybrid-transmitting the first content data using thebroadcast wave and the second content data using the communicationchannel so that the first content data and the second content dataconstitute the content, and when the content is hybrid-transmitted usingthe broadcast wave and the communication channel, the auxiliaryinformation causing a reception side to perform the synchronization whenthe reception side receives the auxiliary information, wherein, in thetransmitting of the auxiliary information by the transmitter, theauxiliary information includes attribute information indicating that thefirst content data and the second content data constitute the contentand location information that indicates an acquisition destination ofthe content or information indicating an acquisition destination of thelocation information, the first content data and the second content dataare (i) identical data each indicating the content, or (ii) video data,audio data, or video and audio data that constitute the content, and theauxiliary information also includes information indicating a format ofmeta-information on playback control of the content transmitted usingthe communication channel, the meta-information on the playback controlincluding information on scalability between streams.
 8. A receptiondevice comprising: a receiver that receives content hybrid-transmittedas a first content data transmitted using a broadcast wave and a secondcontent data transmitted using a communication channel; and a playerthat plays back the content transmitted using the broadcast wave and thecontent transmitted using the communication channel by synchronizing thefirst content data transmitted using the broadcast wave and the secondcontent data transmitted using the communication channel so that thefirst content data and the second content data constitute the content,when auxiliary information for synchronizing the content transmittedusing the broadcast wave and the content transmitted using thecommunication channel is received, wherein, in the playback by theplayer, the content is played back while the synchronization isperformed, when the auxiliary information including attributeinformation indicating that the first content data and the secondcontent data constitute the content and location information thatindicates an acquisition destination of the content or informationindicating an acquisition destination of the location information isreceived in the receiving step, the first content data and the secondcontent data are (i) identical data each indicating the content, or (ii)video data, audio data, or video and audio data that constitute thecontent, and the auxiliary information also includes informationindicating a format of meta-information on playback control of thecontent transmitted using the communication channel, themeta-information on the playback control including information onscalability between streams.
 9. The transmission method according toclaim 1, wherein the first content data is basic layer data of (i) videoand audio data indicating the content or (ii) video data, audio data, orvideo and audio data that constitute the content, and the second contentdata is extended layer data of (i) the video and audio data indicatingthe content or (ii) the video data, the audio data, or the video andaudio data that constitute the content.
 10. The transmission methodaccording to claim 1, wherein the attribute information includesinformation for identifying that an asset of the first content data andan asset of the second content data are related to each other.